swan-flower vs swan-neck

swan-flower and swan-neck both are nouns.

Word	Noun	Adjective	Verb	Adverb
swan-flower	Yes	No	No	No
swan-neck	Yes	No	No	No

As nouns, swan-flower and swan-neck are synonyms defined as:

swan-flower and swan-neck: any of several orchids of the genus Cycnoches having slender arching columns of flowers suggesting the neck of a swan

Other synonyms of swan-flower include swan orchid, swanflower, swanneck.

swan-flower (noun)	swan-neck (noun)
any of several orchids of the genus Cycnoches having slender arching columns of flowers suggesting the neck of a swan	any of several orchids of the genus Cycnoches having slender arching columns of flowers suggesting the neck of a swan