What a lot of people need to put on.

"Put on your big kid/girl/boy pants" means that the person who is being referred to is being immature and childish and won't man up.
"Matt challenged Jim to a fight for insulting his mother."

"I heard he wasn't going to show."

"Really? Jim needs to put on his big kid pants and take responsibility for his stupid actions."
by RoseRoseRose454684565968968456 October 23, 2009
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