festoonery vs flower chain

festoonery and flower chain both are nouns.

Word	Noun	Adjective	Verb	Adverb
festoonery	Yes	No	No	No
flower chain	Yes	No	No	No

As nouns, flower chain is a hypernym of festoonery; that is, flower chain is a word with a broader meaning than festoonery:

festoonery: flower chains suspended in curves between points as a decoration
flower chain: flowers strung together in a chain

festoonery (noun)	flower chain (noun)
flower chains suspended in curves between points as a decoration	flowers strung together in a chain