starting gate vs starting stall

starting gate and starting stall both are nouns.

Word	Noun	Adjective	Verb	Adverb
starting gate	Yes	No	No	No
starting stall	Yes	No	No	No

As nouns, starting gate and starting stall are synonyms defined as:

starting gate and starting stall: a movable barrier on the starting line of a race course

starting gate (noun)	starting stall (noun)
a movable barrier on the starting line of a race course	a movable barrier on the starting line of a race course