Acute means keen. example He was very acute or keen of hearing.
Concieve meens think of. example. he conceived the idea or thought of it in 1867. P.S. that date is random its not important from my knowledge.
Vex means to annoy. Example. He was vexed or annoyed by the situation.
Stifled means to smother. Example. He was being stifled or smothered.
Crevice means crack. Example. He fell in the crevice or crack in the ice.
I hope this helps.