The phrase "put weight" can have several synonyms, depending on the context and usage. Some popular synonyms include "gain weight," "add weight," "put on pounds," "increase body weight," "bulk up," and "put on mass." These terms are often used interchangeably in conversations about weight gain or bodybuilding. Depending on the tone and goal of the conversation, some synonyms may be considered more appropriate or effective than others. Regardless of the synonym used, the goal is often the same: to describe the process of adding weight or mass to one's body.