WordNet sense 1 (a padded cloth covering to keep a teapot warm):

cosy, cosey, cozey, cozie, tea cosey, tea cosy, tea cozey, tea cozie, tea cozy

WordNet sense 2 (having or fostering a warm or friendly and informal atmosphere):

informal, intimate, intimate

WordNet sense 3 (characteristic of or befitting a friend):

friendly

WordNet sense 4 (enjoying or affording comforting warmth and shelter especially in a small space):

snug

WordNet sense 5 (providing or experiencing physical well-being or relief (`comfy' is informal)):

comfortable, comfy

WordNet sense 6 (close in relevance or relationship):

close