疑う, うたがう
Conjugated: 疑え
Godan verb, Transitive
to doubt, to distrust, to be suspicious of, to suspect
ぼくのことばをまだ疑っているんですか。
七度尋ねて人を疑え, ななたびたずねてひとをうたがえ, しちどたずねてひとをうたがえ
Expression, Proverb
search thoroughly for something lost before you suspect someone of stealing it, be on sure ground before you accuse somebody