morale builder vs morale booster

morale builder and morale booster both are nouns.

Word	Noun	Adjective	Verb	Adverb
morale builder	Yes	No	No	No
morale booster	Yes	No	No	No

As nouns, morale builder and morale booster are synonyms defined as:

morale builder and morale booster: anything that serves to increase morale

Other synonyms of morale builder include morale building.

morale builder (noun)	morale booster (noun)
anything that serves to increase morale	anything that serves to increase morale
something or someone who influences by building or strengthening morale