What does "reed organ" mean?

A keyboard musical instrument of which the harmonium and the American organ are the principal types.

What is a synonym for "reed organ"?

Common synonyms include: calliope, harmonium, melodeon, organ.

noun

noun ·Rare ·Advanced level

Noun

1
A keyboard musical instrument of which the harmonium and the American organ are the principal types.
2
a free-reeded instrument with a piano keyboard in which air is forced through the reeds by bellows wordnet