i-adjective
unjustly suspicious; prone to groundless suspicion
Describes a person who habitually suspects others without good reason, often seeing malice or hidden motives where none exist. The word is relatively rare and literary in tone.
彼は邪推深い人で、友達の親切も裏があると疑ってしまう。
He is an unjustly suspicious person, suspecting even his friends' kindness of having ulterior motives.
疑い深い means 'deeply suspicious' in a general sense, while 邪推深い specifically implies unjust or groundless suspicion, often with a negative moral judgment.
Compound of 邪推 (じゃすい, 'unjust suspicion') and 深い (ふかい, 'deep'). The exact historical derivation is uncertain, but the word follows a common pattern of adjective formation.