The phrase "kept lid on" typically means to keep something under control or to keep a secret. Antonyms for this phrase could include "unleashed," "revealed," "exposed," "uncovered," or "unveiled." If someone has kept a lid on their emotions or thoughts, the antonyms would be "expressive," "open," "forthcoming," "outspoken," or "uninhibited." In a business or political context, the antonyms might be "freed," "decentralized," "democratized," or "empowered," referring to the idea of removing restrictions or giving people more power or influence. Overall, antonyms for "kept lid on" suggest a need for greater transparency, honesty, and openness.