noun
A deep-seated tendency to suspect others' motives; often used in psychological or literary contexts. 猜疑心が強い is a common collocation.
彼は猜疑心が強くて、なかなか人を信用しない。
He is very suspicious and doesn't trust people easily.
猜疑心から、友人の言葉
Out of suspicion, I couldn't take my friend's words at face value.
嫉妬 is jealousy or envy, often in romantic or competitive contexts. 猜疑心 can include jealousy but emphasizes distrust of others' intentions.
猜疑 (suspicion) + 心 (heart/mind). 猜疑 is a compound of 猜 (envy, jealousy) and 疑 (doubt).