cosey / cosy / cozy 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. 👇
cosey: NA
cosy: (noun) a padded cloth covering to keep a teapot warm.
cozy: (adjective) enjoying or affording comforting warmth and shelter especially in a small space. (adjective) having or fostering a warm or friendly and informal atmosphere. (adjective) suggesting connivance.
cosey: k·OW·z·iy
cosy: k·OW·z·iy
cozy: k·OW·z·iy
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)