synodic month vs lunation

synodic month and lunation both are nouns.

Word	Noun	Adjective	Verb	Adverb
synodic month	Yes	No	No	No
lunation	Yes	No	No	No

As nouns, synodic month and lunation are synonyms defined as:

synodic month and lunation: the period between successive new moons (29.531 days)

Other synonyms of synodic month include lunar month, moon.

synodic month (noun)	lunation (noun)
the period between successive new moons (29.531 days)	the period between successive new moons (29.531 days)