The Elven language, or "Elvish", was largely lost when Elvhenan fell to the Tevinter Imperium and its people were enslaved around two millennia before the Dragon Age. When the elves settled their second homeland, the Dales, they aimed to restore their lost language and lore, but the Dales fell after an Exalted March declared by the Chantry in the early Glory Age. The Elvish of the Dragon Age is thus a fragmented remnant, a few words that are thrown into conversation rather than a working language used to conduct everyday life. The Dalish Elves, self-appointed custodians of the elven language and lore, use more Elvish than their City Elf brethren. Living among humans, the City Elves now retain only a few old Elvish words whose origin is almost forgotten, such as "shem" - derived from "shemlen", meaning "quickling", or "quick children" the old Elvish term for humans - and "hahren" - the leader of an Alienage, meaning "elder" in Elvish.
With the release of Dragon Age II, and Merrill's speech patterns, it has been determined that pronouns most likely carry an implied possessive. What this means for translation is that words like "ma" and "ar" can carry a "have" with them - "you have", "I have" - without actually needing to add in the "have" as a separate word.
The spelling system for Elvish contains an apostrophe to mark register tone, not to mark stress or to decorate text as per the usual usage of the apostrophe. Also indicates contraction points between two full words that cannot be reduced by adjoining letters.
Many of the words in the following list are extrapolations and deconstructions of words found in the game, done by parsing the order of meanings versus given words and comparisons of fragments to the meanings given.
Canon: Elvish Phrases
- Andaran atish’an (ahn-DAHR-ahn ah-TEESH-ahn): Enter this place in peace. A formal elven greeting. Literally: "I dwell in this place, a place of peace."
- Aneth ara (AH-neth AH-rah): A sociable or friendly greeting, more commonly used among the Dalish themselves rather than with outsiders. Literally: "My safe place".
- Arlathan (ahr-LATH-ahn): The major city of Elvhenan, original homeland of the elves, from the phrase "ar lath’an" meaning "I love the place".
- Dareth shiral (da-RETH shee-RAL): Often said by Lanaya in the Dalish Camp. Used as a "farewell" it means, "safe journey".
- Elvhenan (EL-vehn-ahn): Place of our people. The name of the elven civilization before the arrival of humans in Thedas. Also could be translated as: "Our hearts".
- Ma nuvenin (mah noo-VEY-nihn): As you wish.
- Ma serannas (ma SEHR-ahn-ahs): My thanks (Thank you.).
- "Mamae? Mamae na mara san...": Spoken by the ghostly boy.
- "Viran se lan'aan? Ir annala for ros... Nae! Ga rahn s'dael! Ga rahn! Ir emah'la shal! Ir emah'la shal!": Spoken by the ghostly elven mother in the crypt where you get the Juggernaut armour. See "Deconstructing Elvish", below, for details on both ghosts' possible meanings.
Canon: The Elvish Eulogy
hahren na melana sahlin
elder your time is come
—From Codex entry: In Uthenera
(It's interesting to note, too, that these are the lyrics to the song Leliana sings for you in camp during Origins gameplay.)
Canon: Suledin (Endure) an Elven Song
The elven song Suledin is played during the dungeon escape portion of the Leliana's Song DLC. The song is about enduring and emerging from sorrow, tied to the elves' loss of their ancient lands. It is adapted to personal struggles, as well. 
Melava inan enansal
Time was once a blessing
Translator's Note: This has got to be a loose translation, at best. For instance, we know "lath" means "love", and yet "lath aravel ena" is translated as "and the path will emerge".
Note: Another very gifted linguist, Katiebour, has also taken a stab at translating Elvish, and her dictionary has insights and alternatives to what's been written here that are worth checking out. It can be found at http://archiveofourown.org/works/359253/chapters/582281.
- Abelas (ah-BEY-lahs): Sorrow. Also used as an apology.
- Adahl (ah-DAHL): tree.
- Adahlen (AH-dah-len): forest.
- Alas (AH-lahs): earth, dirt.
- An (AHN): place or location.
- Annar (AN-ahr): year.
- Ar (AHR): personal pronoun: I, me.
- Aravel (AHR-ah-vehl): long journey.
- Arla (AHR-lah): home.
- Arlathvhen (ahr-LATH-vehn): Meeting of the Dalish clans, every ten years. 
- Asha (AH-sha): woman.
- Assan (ah-SAHN): arrow.
- Atisha (ah-TEE-shah): peace, peaceful.
- Bel (BELL): many.
- Bora (BOHR-ah): to throw, project, loose.
- Bor'assan (BOHR-ah-sahn): bow.
- Da (DAH): small, diminutive prefix.
- Dar (DAHR): to be.
- Da'len (dah-LEN): little child.
- Dareth (dah-RETH): be safe.
- Din (DEEN): not, or isn't; also used to indicate someone who has died: someone who is not.
- Dirth (DEHRTH): tell, speak.
- Dorf (DOHRF): grey.
- Durgen (DUHR-jen): stone.
- Durgen’len (dur-JEN-len): Children of the stone. The original Elvish term for the dwarves.
- El (EHL): our.
- Elgar (EHL-gahr): spirit.
- Eluvian (ehl-LOO-vee-ehn): mirror.
- Elvarel (EHL-vah-rehl): longer, more effort.
- Elvhen (EHL-vehn): "Our People". Elven name for their own race.
- Elvhenan (EHL-vehn-ahn): Place of our people. The name of the elven civilization before the arrival of humans in Thedas. Also could be translated as: "Our hearts".
- Emma (EM-mah): I am.
- -en (EHN): suffix indicating plural.
- Ena (eh-NAH): appear; emerge.
- Enasal (EHN-ah-sahl): repeat
- Enansal (en-AHN-sahl): gift or blessing.
- Era (EH-rah): story, tale, dream.
- Falon (fah-LOHN): friend.
- Felas (FAY-lahs): slow.
- Fen (FEHN): wolf.
- Halam (hah-LAHM): the end, finished.
- Hahren (hah-REHN): Elder. Used as a term of respect by the Dalish, but more specifically for the leader of an alienage by the City Elves.
- Halamshiral (hah-LAHM-sheer-AHL): The end of the journey. Also the name of the capital of the second elven homeland in the Dales.
- Hamin (hah-MEEN): rest, relax. Deconstructing: "mi": blade; "in": inside. 'Sheath your knife'?
- Harel (hah-REHL): dreaded, frightening, causing fear.
- Him (HEEM): becomes.
- In (EEN): with or inside; dwell.
- Inan (ee-NAHN): eyes. Literally: "inside place" or "dwelling place" - i.e. windows to the soul.
- Ir (EER): very, more.
- Isala (ee-SAH-lah): in need of.
- Lath (LAHTH): love.
- Len (LEHN): child.
- Lethallin; Lethallan (leth-ah-LEEN; leth-ah-LAHN): Casual reference used for someone with whom one is familiar. Lethallin is used for males, while lethallan is used for females. Akin to "cousin" or "clansman" since "lin" is the word for blood. See talk page for more information.
- Lin (LEEN): blood.
- Ma (MAH): my, mine.
- Mahvir (mah-VEER): tomorrow.
- Mamae (mah-MAY): Mother.
- Mana (MAH-nah): distant past; long amount of time.
- Melana (meh-LAH-nah): time.
- Melava (meh-LAH-vah): time, past tense.
- Mi (MEE): blade.
- Na (NAH): your.
- Nan (NAHN): revenge; vengeance.
- Nehn (NEN): joy.
- Numin (NOO-min): cry, tears.
- Nuvenin (noo-VAY-nin): want, need.
- Reth (REHTH): safety.
- Revas (RAY-vahs): freedom.
- Sa (SAH): one.
- Sahlin (sah-LEEN): now, in this moment.
- Samahl (sah-MAHL): laugh, laughter.
- Sa'vunin (sah-VOO-neen): a single day.
- Serannas (SEHR-ah-nahs): grateful, appreciative.
- Seth (SEHTH): thin, tenuous.
- Setheneran (SEH-thehn-ERR-ahn): Land of waking dreams. A place where the Veil is thin. Literally: "Tenuous waking dream place"
- Shem (SHEHM): quick, fast.
- Shemlen (SHEHM-lehn): Literally "quick children". The original name of the elves for the human race. It continues to see use as a slang term amongst the City Elves ("Shems") even though its meaning has largely been lost.
- Shiral (shee-RAHL): journey.
- Souveri (soo-VEH-ree): weary, tired.
- Su (soo): happen.
- Sulahn (soo-LAHN): sing.
- Suledin (soo-leh-DEEN): endure.
- Sulevin (soo-leh-VEEN): certain.
- Tan (TAHN): three.
- Then (THEN): awake, alert.
- Tu (tooh): to make, to cause.
- U (ooh): alone.
- Uth (OOTH): long, forever, never ending, eternal.
- Uthenera (ooth-en-ERR-ah): Waking sleep. Uthenera was the name of the ancient practice of immortal elves who would "sleep" once they tired of life. Literally: "Eternal waking dream".
- Vallas (VALL-ahs): writing.
- Vallaslin (vahl-ahs-LEEN): Blood writing. The art of tattooing adopted by some elves to more prominently (and some might say belligerently) display their worship of the traditional elven pantheon.
- Ven (VEHN): to go.
- Vhen (VEHN): "people of" or "belonging to the elves, the clans, elven society".
- Vhenadahl (vehn-AH-dahl): The tree of the people.
- Vhen'alas (vehn-AHL-ahs): The land itself, as in "the ground". Literally: "our earth".
- Vhenan (VEY-nahn): heart.
- Vir (VEER): way or path. 
- Vunin (VOO-nihn): day.
Constructing Elvish: Examples of Phrases
- da'assan (dah-ah-SAHN): little arrow
- da'mi (dah-MEE): little blade
- da'vhenan (dah-VEY-nahn): little heart
- emm'asha (ehm-AH-shah): my girl
- emma lath (EHM-mah lath): my love
- ma sa'lath (mah sah-lath): my one love
- emma vhenan (EHM-ma VEY-nahn): my heart
- ma'arlath (MAR-lath): I love you
- ma emma lath (ma EHM-mah lath): you are my love
- vhenan'ara (VEY-nahn-AHR-ah): heart's desire
- elvhen'alas (el-VEHN-ALL-us): dirt elves
- len'alas lath'din (len-ALL-us LATH-deen): dirty child no one loves
- seth'lin (seth-LEEN): thin blood
- Ar'din nuvenin na'din. (ahr-DEEN noo-VHEY-nihn nah-deen): I don't want to kill you.
- Ar tu na'din. (ahr too nah-DEEN): I will kill you.
- Ar tu na'lin emma mi. (ahr too nah-LEEN EHM-ma mee): I will see your blood on my blade.
- Emma shem'nan. (EHM-mah shem-NAHN): My revenge is swift.
- Halam sahlin. (hah-LAHM sah-LEEN): This ends now.
- Ma emma harel. (mah EHM-mah hah-REHL): You should fear me.
- Ma halam. (mah hah-LAHM): You are finished.
Many words of Elvish are made up of contractions of smaller words. For instance, "Arlathan" means, "this place that I love". Deconstructing it, we arrive at Ar: I or me; Lath: love; and An: place. We know that this is correct, because: "lath" is used later in the eulogy poem to mean "love"; "an" is seen as a suffix in the word "Elvhenan", meaning "the place of our people", which is a direct extension of "Elvhen", meaning "our people". By elimination, "Ar" becomes the personal pronoun. In the same way, many of the other words we see can be deconstructed into their individual components.
- "Mamae? Mamae na mara san...": The panicked phrases of a lost child. We already know "mamae" means "mother", and "na" is "your". "Mara" and "san" are a different matter. "Ma" (you) and "ar" (i, me) don't give us much clue. "San" looks like a contraction of "sa" and "an", so, one place. Since the boy seems to be in a panic, and we've already surmised he's looking for her, it's reasonable to assume that this is the gist of his statement, as well. So, we have "Mother your [mara] one place...", which we can then parse "mara" as "i can't find" or "where is". So, a reasonable translation would be, "Mama, I can't find you..." or "Mama, where is the place..."
- "Viran se lan'aan? Ir annala for ros... Nae! Ga rahn s'dael! Ga rahn! Ir emah'la shal! Ir emah'la shal!": These sentences are spoken by the ghostly elven mother in the crypt where you get the Juggernaut armour. Best guess at translation: "How did you people find the path to this place? This place has been lost for centuries. No! Get away from our tree! Get away! You are desecrating my grave! You are desecrating my grave!"
- "Viran se lan'aan?": We know that "vir" and "an" mean "the path" and "this place", respectively, so we have "the path to this place". If we assume that "se" is a pronoun (since "lan'aan" is a bit long for that), then, going off of "sa" as "one" and "-en" as a plural, we could extrapolate "se" as possibly a plural "you". In that case, since it is a question, we could assume she is asking "How did you people find the path to this place?", since that is a reasonable thing to be asking. Then, "lan'aan" would mean "how to find". However, it could also contain an element of time, as the words "melana" (time) and "annar" (years), or another element of place, "an".
- "Nae! Ga rahn s'dael! Ga rahn!": This is a very difficult part, because there's so little to go on. "Nae" might be "no", but "na" means "your". There is no precedent for "ga rahn", but "s'dael" could be broken down as: "sa" - one; "adahl" - tree; and "el" - our. Taking that on faith, the sentence might read something like, "No! Get away from our tree! Get away!"
- "Ir annala for ros...": We know that "ir" means "very", and "annar" is "years", so it is reasonable to assume that "annala" has to do with a measurement of time in years. Perhaps it means "centuries". So, it begins with "A very many years or centuries", and then "for ros" has no precedent. Taking it together with the last line, it is highly probable that it means "This place has been lost for very many centuries."
- "Ir emah'la shal!": "ir" (very). Deconstructing "emah'la": "emma" (my); "alas" (dirt, earth); "halam" (ending); "shiral" (journey) - all of these words contain elements similar to this compound word. As an educated guess, I'm thinking it means "the ground of my end", or, more loosely, "my grave". So, "My grave is very..." something. Perhaps "shal" means sacred, or desecrated. So, loosely, "You are desecrating my grave!"
- "Dar'Misu; Dar'Misaan": "Dar" means "to be", and they both have "mi" in common, so it is possible that "mi" is "blade", and we know that "su" means "happen", and "u" means "alone". So, "dar'misu" could translate, roughly, to "this blade acts alone" or "this blade happens". "Sa" is "one" and "an" is "place". Best guess: Dar'Misu: "to be a blade that acts alone" - daggers being the weapon of choice for rogues; Dar'Misaan: "to be a blade of one place" - long swords being the weapon of choice for a sword-and-shield defender.
In Dragon Age: The Stolen Throne (Page 75) the Dalish elves who captured Maric and Loghain claimed to speak mostly in elvish except for those who traded with humans saying: "Here in the clan, we try to keep our own tongue alive, just as we do our gods."