If you feel sheepish, you feel a little uncomfortable or embarrassed because you know you have done something silly or wrong — not a huge crime, more “you caught me.” The face that goes with it is often a small, guilty smile. People talk about a sheepish grin, a sheepish look, a sheepish laugh. The picture behind the word is a sheep: timid, easily led, not proud. The feeling is mild. You can be sheepish about eating the last biscuit or forgetting a name; you would not usually call deep shame or real grief sheepish. Neutral to informal; common in stories and everyday talk. Though actually, students sometimes think sheepish means “like a sheep” in the sense of following the crowd. English mostly uses sheepish for that embarrassed look, not for blind following.