jealous

adjective

Envious or resentful of the good fortune or achievements of another.

adjective

Fearful or wary of losing one’s position or situation to someone else, especially in a sexual relationship.

adjective

Having to do with or arising from feelings of envy, apprehension, or bitterness.

adjective

Vigilant in guarding something.

adjective

Intolerant of disloyalty or infidelity; autocratic.

To suspect; distrust.

Full of zeal; zealous in the service of a person or cause; solicitous for the honor or interests of one’s self or of another, or of some institution, cause, etc.: followed by for.

Anxiously watchful; suspiciously vigilant; much concerned; suspicious.

Specifically Troubled by the suspicion or the knowledge that the love, good will, or success one desires to retain or secure has been diverted from one’s self to another or others; suspicious or bitterly resentful of successful rivalry: absolute or followed by of with an object: as, a jealous husband or lover; to be jealous of a competitor in love or in business, of one’s mistress, or of the attentions of others toward her.

Fearful; afraid.