canvases / canvasses are similar-sounding terms with different meanings (referred to as homophones). To better understand the differences, see below for definitions, pronunciation guides, and example sentences using each term. 👇
canvases: (noun) a heavy, closely woven fabric (used for clothing or chairs or sails or tents). (noun) an oil painting on canvas fabric. (noun) the setting for a narrative or fictional or dramatic account. (noun) the mat that forms the floor of the ring in which boxers or professional wrestlers compete. (verb) cover with canvas.
canvasses: (verb) solicit votes from potential voters in an electoral campaign.
canvases: k·AE·n·v·ah·s·ih·z
canvasses: k·AE·n·v·ah·s·ih·z
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)