short-term memory vs STM

short-term memory and STM both are nouns.

Word	Noun	Adjective	Verb	Adverb
short-term memory	Yes	No	No	No
STM	Yes	No	No	No

As nouns, short-term memory and STM are synonyms defined as:

short-term memory and STM: what you can repeat immediately after perceiving it

Other synonyms of short-term memory include immediate memory.

short-term memory (noun)	STM (noun)
what you can repeat immediately after perceiving it	what you can repeat immediately after perceiving it