fattening /ˈfæt(ə)nɪŋ/noun 2adjective 1forms 3 noun2 •The act of making something fatter, particularly in reference or allusion to livestock. •The act of becoming fatter. adjective1 •That causes weight gain; often of high calorie food with relatively little nutritive value.I'd really love to lose weight, the trouble is, tasty desserts with stuff like whipped cream are so fattening. formsfattenings · more fattening · most fattening