The word "chucker" has a few different meanings and connotations that can be expressed through different synonyms. As a noun, it can refer to a person who throws or chucks something, so synonyms might include hurler, tosser, or flinger. However, "chucker" can also be used as a derogatory term for a person who quits or quits prematurely, in which case synonyms might include quitter, deserter, or dropout. In a different context, "chucker" can refer to a game of polo, where it denotes a period of play lasting seven and a half minutes, in which case other terms might be chukka or chuck. Depending on the context, there are several ways one might replace the word "chucker" to get the desired effect or meaning.