When someone is "laying it thick", they are exaggerating or overemphasizing something. Antonyms for this phrase could include "downplaying", "understating", "minimizing", or "reducing". These words imply that instead of making something seem bigger or more important than it is, the person is making it seem less significant or noteworthy. For example, instead of laying it thick by saying a movie was the best one ever made, one could understate by simply saying it was enjoyable. By using these antonyms, you can communicate a more tempered response without the risk of sounding like you are trying to impress or over-inflate your opinion.