ham it up
to perform with too much false emotion when acting

[TahlilGaran] Dictionary of Contemporary English ▲

ham it up
to show expressions or emotions more obviously than is realistic.
Here's a picture of Philip hamming it up for grandma when he was only three.

Usage notes: usually said about expressions made to amuse others
Etymology: based on the literal meaning of ham (= an actor who performs with very obvious emotions and expressions)

[TahlilGaran] English Idioms Dictionary ▲

ham it up
do something silly or try to exaggerate something in a funny way
I was hamming it up with my friend in front of the principal's office.

[TahlilGaran] English Idioms Dictionary ▲

ham it up
v. phr., slang To do more than look natural in acting a part; pretend too much; exaggerate.
When Tom told the teacher he was too sick to do homework, he really hammed it up.
The old-fashioned movies are funny to us because the players hammed it up.
Compare: LAY IT ON.

[TahlilGaran] English Idioms Dictionary ▲