Quenya 

lintië

swiftness, speed

lintië noun "swiftness, speed" derived from linta; also used as adverb "quickly", nornë lintië "he ran with swiftness", also more explicitly with pronominal suffixes and the instrumental ending -nen: lintieryanen "with his speed" (PE17:58)

lintië

noun/adverb. swiftness, speed; swiftly, *quickly

Quenya [PE17/058; PE17/059] Group: Eldamo. Published by

linta

swift

linta adj. "swift"; pl. lintë attested (PE17:63. Nam, RGEO:66) Cf. lintië.

linta

adjective. swift

Quenya [LotR/0377; PE17/059; PE17/063; PE17/076; PE17/147; RGEO/58] Group: Eldamo. Published by

-nen

most nouns have an instrumental in -nen

-nen instrumental ending (pl. -inen, dual -nten, partitive pl. -línen). Attested in ambartanen, lírinen, lintieryanen, súrinen, parmanen; see ambar (#2), lírë, lintië, súrë, parma. Tolkien noted that "most nouns have an instrumental in -nen" (PE17:62), a wording suggesting that the form of the ending may vary; given the normal development ln > ld, it is possible that it would appear as *-den when added to a noun in -l (*macilden "with a sword").

nornë lintië

he ran quickly

Quenya [PE17/058; PE17/059] Group: Eldamo. Published by

alarca

swift, rapid

alarca ("k")adj. "swift, rapid" (LAK2)

arauca

swift, rushing

arauca ("k")adj. "swift, rushing" (LT2:347). Compare arauco.

larca

swift, rapid

larca ("k")adj. "swift, rapid" (LAK2)

rindë

adjective. swift

tyelca

swift, agile

tyelca ("k")adj. "swift, agile" (KYELEK), "hasty" (PM:353)