im ‧ be ‧ cile /ˈɪmbəsiːl $ -s ə l/ BrE AmE noun [countable]
[ Date: 1400-1500 ; Language: French ; Origin: imbécile , from imbécile 'weak, weak-minded' , from Latin imbecillus , probably from baculum 'stick (for support)' ]
someone who is very stupid or behaves very stupidly SYN idiot :
He looked at me as if I was a total imbecile.
—imbecilic /ˌɪmbəˈsɪlɪk◂, ˌɪmbɪˈsɪlɪk◂/ adjective
—imbecility /ˌɪmbəˈsɪləti, ˌɪmbɪˈsɪləti/ noun [uncountable and countable]