The Oxford Thesaurus An A-Z Dictionary of Synonyms - pep n.

1) vigour, vim (and vigour) , spirit, animation, vivacity, energy, verve, zest, fire, sprightliness, life, effervescence, sparkle, ebullience, dash, enthusiasm, brio, ‚lan, Colloq zip, zing: He certainly has a lot of pep for an octogenarian. --v. 2) pep up. stimulate, invigorate, animate, enliven, vitalize, vivify, energize, exhilarate, quicken, arouse, breathe (some) life into, inspire, activate, actuate, fire, cheer up, Colloq buck up, spark, work or fire up, US wind up: After those defeats, the team needed to be pepped up.