stirrup iron vs saddle

stirrup iron and saddle both are nouns.

Word	Noun	Adjective	Verb	Adverb
stirrup iron	Yes	No	No	No
saddle	Yes	No	Yes	No

stirrup iron (noun)	saddle (noun)
support consisting of metal loops into which rider's feet go	posterior part of the back of a domestic fowl
	a seat for the rider of a horse or other animal
	a seat for the rider of a bicycle
	a piece of leather across the instep of a shoe
	cut of meat (especially mutton or lamb) consisting of part of the backbone and both loins
	a pass or ridge that slopes gently between two peaks (is shaped like a saddle)

stirrup iron (verb)	saddle (verb)
	impose a task upon, assign a responsibility to
	put a saddle on
	load or burden; encumber