For the musical by Julian Slade, see: Salad Days.

"Salad days" is an idiomatic expression, referring to a youthful time, accompanied by the inexperience, enthusiasm, idealism, innocence, or indiscretion that one associates with a young person. More modern use, especially in the United States, refers to a person's heyday —when somebody was at the peak of their abilities—not necessarily when they were young

The phrase was coined in Shakespeare's Anthony and Cleopatra in 1606. In the speech at the end of Act One in which Cleopatra is regretting her youthful dalliances with Julius Caesar she says:

"...My salad days, / When I was green in judgment, cold in blood..."

The phrase only became popular from the middle of the nineteenth century on, coming to mean “a period of youthful inexperience or indiscretion." The metaphor comes from the Cleopatra's use of the word 'green'—a word which has a meaning indicating someone youthful, inexperienced, or immature.