Something, usually a quick drink or
snack, that provides a burst of energy or restores your nerves.
People may say they need a 'pick-me-up' if they are having a long, busy
day and need to renew their energy. A pick-me-up might be a cup of
coffee or Coke or a candy bar.
I've been out with the kids all day. Before going to the concert, I
could use a quick pick-me-up.