trim down vs trim back

trim down and trim back both are verbs.

Word	Noun	Adjective	Verb	Adverb
trim down	No	No	Yes	No
trim back	No	No	Yes	No

As verbs, trim down and trim back are synonyms defined as:

Other synonyms of trim down include bring down, cut, cut back, cut down, reduce, trim.

trim down (verb)	trim back (verb)
cut down on; make a reduction in	cut down on; make a reduction in