fat-ass in English dictionary fat-ass Meanings and definitions of "fat-ass" (vulgar, slang, pejorative) A rotund, overweight, or obese person. (pejorative) A jibe used on someone disliked, frequently someone regarded as lazy. noun (vulgar, slang, pejorative) A rotund, overweight, or obese person. noun (pejorative) A jibe used on someone disliked, frequently someone regarded as lazy. (Pejorative) A fat or overweight person. more Grammar and declension of fat-ass fat-ass ( plural fat-asses) fat-ass (plural fat-asses) more Images with "fat-ass" Sample sentences with "fat-ass" Declension Stem Try again Available translations Afrikaans Armenian Bench Chinese Colognian Czech Dutch Esperanto Finnish French German Greek Hungarian Italian Japanese Macedonian Maori Polish Portuguese Russian Spanish Swedish Authors