mat / matt / matte 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. 👇
mat: (noun) a thick flat pad used as a floor covering. (noun) mounting consisting of a border or background for a picture. (noun) sports equipment consisting of a piece of thick padding on the floor for gymnastic sports. (noun) a mass that is densely tangled or interwoven. (noun) a small pad of material that is used to protect surface from an object placed on it.
matt: NA
matte: (noun) a mixture of sulfides that forms when sulfide metal ores are smelted.
mat: m·AE·t
matt: m·AE·t
matte: m·AE·t
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)