asinine (adj.)

• absurd
• airy
• apish
• batty
• beguiled
• besotted
• blockish
• bovid
• bovine
• brainless
• buffoonish
• caprine
• catchpenny
• cloddish
• cockeyed
• crass
• crazy
• credulous
• daft
• dazed
• dense
• dizzy
• doltish
• doting
• dumb
• duncical
• duncish
• empty
• equestrian
• equine
• fat
• fatuous
• flaky
• flimsy
• fond
• foolish
• frivolous
• frothy
• fuddled
• futile
• gaga
• goofy
• gross
• hircine
• hoggish
• hoofed
• idiotic
• idle
• imbecile
• inane
• inept
• infatuated
• insane
• irrational
• kooky
• light
• loony
• lumpish
• mad
• maudlin
• mindless
• moronic
• mulish
• nugatory
• nutty
• oafish
• opaque
• otiose
• ovine
• piggish
• puerile
• ruminant
• sappy
• screwy
• senseless
• sentimental
• shallow
• sheepish
• sheeplike
• silly
• slender
• slight
• sottish
• stupid
• superficial
• swinish
• thick
• thoughtless
• trifling
• trite
• trivial
• ungulate
• unreasonable
• vacuous
• vain
• vapid
• wacky
• wet
• windy
• witless
• wrongheaded