/pep"euhr up"euhr/ , n. Informal.
1. something, as a food, beverage, or pill, that provides a quick but temporary period of energy and alertness.
2. something added to food to relieve blandness.
3. an experience that increases enthusiasm or zeal, as a pep talk.
Also, pepper upper .
[ 1935-40; pep up + -ER 1 , suffixed pleonastically to both v. and particle ]