be born yesterday

Easily fooled innocent

To be born yesterday is to be naive or easily fooled—someone lacking experience or worldly knowledge.

Almost always appears in the negative: I wasn't born yesterday means I'm not gullible enough to believe that.

Do you think I was born yesterday? challenges an obvious lie or manipulation.

Related

inexperienced · credulity · wet behind the ears · unsophisticated · unworldliness · innocence · fresh off the boat · taken for a ride · taken in · childlikeness · ignorance · susceptibility · not the sharpest tool in the shed · easy mark · sucker · simplicity · childbirth · wide-eyed

Opposites
experience and worldliness

be born yesterdayknow the ropes

Understand how things work

know the score · worldly-wise · nobody's fool · have been around · know what's what

susceptibility to deception

be born yesterdayhave one's wits about one

Remain mentally sharp, attentive

smell a rat · trust no one

Family

born, yesterday, borne, reborn, rebirth, newborn, firstborn, stillborn, unborn

Familiarity
Top 100,000
Profile
Used worldwide · Timeless · Abstract · Everyday, not technical · Rated G