We found 3 dictionaries that define the word keep one's pecker up:

General (2 matching dictionaries)

1. keep one's pecker up: Merriam-Webster
2. keep one's pecker up: Wiktionary

Slang (1 matching dictionary)

3. keep one's pecker up: English slang and colloquialisms used in the United Kingdom

Definitions from Wiktionary (keep one's pecker up) ▸ verb:  (chiefly British, idiomatic) To remain cheerful; keep smiling. ▸ Words similar to keep one's pecker up ▸ Usage examples for keep one's pecker up ▸ Idioms related to keep one's pecker up ▸ Wikipedia articles (New!) ▸ Words that often appear near keep one's pecker up ▸ Rhymes of keep one's pecker up ▸ Invented words related to keep one's pecker up