Chubbier is a word that is used to describe a person who may have gained some weight or is slightly overweight. However, there are several other synonyms that can be used to describe someone who is chubbier. These synonyms include plump, overweight, roly-poly, pudgy, chunky, portly, curvy, thickset, and ample. The use of these synonyms would depend on the context of the situation and the intended meaning of the word. It is important to remember that these words should be used carefully so as not to cause offence or hurt someone's feelings.