steam organ vs calliope

steam organ and calliope both are nouns.

Word	Noun	Adjective	Verb	Adverb
steam organ	Yes	No	No	No
calliope	Yes	No	No	No

As nouns, steam organ and calliope are synonyms defined as:

steam organ and calliope: a musical instrument consisting of a series of steam whistles played from a keyboard

steam organ (noun)	calliope (noun)
a musical instrument consisting of a series of steam whistles played from a keyboard	a musical instrument consisting of a series of steam whistles played from a keyboard