pep someone up

pep (one) up

To increase or enhance someone's excitement, interest, energy, or alertness. The show was going really poorly until the host came out and pepped the audience up. I think I need some coffee to pep me up.
See also: pep, up

pep someone up

Invigorate someone or cheer someone up, as in This drink will pep you up, or The good news about his recovery pepped us up. [1920s] Both the verb pep and the noun pep, denoting vigor and energy since about 1910, are abbreviations for pepper, a spice with a pungent, biting quality. They also have given rise to pep rally, a meeting to inspire enthusiasm [c. 1940], and pep talk, a speech meant to instill enthusiasm or bolster morale [1920s].
See also: pep, up