introvert :: inclined to think more about oneself
inured :: accustomed; hardened
inverse :: opposite
inveterate :: deep-rooted; habitual
invidious :: designed to create ill will or envy
invulnerable :: incapable of injury
irascible :: irritable; easily angered
iridescent :: exhibiting rainbowlike colors
ironical :: resulting in an unexpected and contrary manner
irreconcilable :: incompatible; not able to be resolved
irrelevant :: not applicable; unrelated
irremediable :: incurable; uncorrectable
irreparable :: not able to be corrected or repaired
irreverent :: lacking proper respect
irrevocable :: unalterable
itinerant :: wandering; traveling
jaded :: fatigued; surfeited
jaundiced :: yellowed; prejudiced; envious
jocose :: giving to joking
jocular :: said or done in jest
jocund :: merry
judicious :: wise; determined by sound judgment
lackadaisical :: affectedly languid
laconic :: brief and to the point
laggard :: slow; sluggish
lambent :: flickering; softly radiant
laminated :: made of thin plates or scales
languid :: weary; sluggish; listless
lascivious :: lustful
latent :: dormant; hidden
lateral :: coming from the side
laudatory :: expressing praise
lavish :: liberal; wasteful
lecherous :: impure in thought and act; lustful; unchaste
lethal :: deadly
lethargic :: drowsy; dull
lewd :: lustful
libelous :: defamatory; injurious to the good name of a person
libidinous :: lustful
licentious :: wanton; lewd; dissolute
limpid :: clear
linguistic :: pertaining to language
lithe :: flexible; supple
livid :: lead-colored; black and blue; enraged
loath :: averse; reluctant
loquacious :: talkative
lucent :: shining
lucid :: bright; easily understood
lucrative :: profitable
lugubrious :: mournful
luminous :: shining; issuing light