Without fat, especially in the senses: made without fat, fat-free.(adjective)
Wiktionary.org : Text is available under the Creative Commons Attribution-ShareAlike License
Use "fatless" in a sentence
"The author devised a new version with butter (my recipe was fatless save for eggs and nuts), leaving my biscotti to remain my small contribution to the ages."
"Her belly and hips were fatless and firm, but even so, she seemed bulky and almost masculine in her carriage."
"I like using grated apple or pear to add moisture and fatless flavour."