The antonyms for the phrase "toss party" can be numerous, depending on the context. If we are talking about social gatherings, some of the antonyms can be quiet evening, study session, individual activities, or stay-at-home night. However, if we are discussing the act of discarding or throwing something away, antonyms for toss party can be collecting day, sorting, or organizing items. In a cooking or culinary context, antonyms for toss party can be baking or slowly simmering scrumptious dishes. In a broader sense, antonyms for toss party can be abstain, withhold, restrain, or conserve. While partying and throwing something away may seem like opposite ideas, the antonyms for the phrase can clarify, depending on the intended meaning.