lamentation vs reflexion

lamentation and reflexion both are nouns.

Word	Noun	Adjective	Verb	Adverb
lamentation	Yes	No	No	No
reflexion	Yes	No	No	No

As nouns, reflexion is a hypernym of lamentation; that is, reflexion is a word with a broader meaning than lamentation:

Other hypernyms of lamentation include activity, expression, manifestation, reflection.

lamentation (noun)	reflexion (noun)
the passionate and demonstrative activity of expressing grief	the image of something as reflected by a mirror (or other reflective material)
a cry of sorrow and grief	the ability to reflect beams or rays
	a likeness in which left and right are reversed
	a calm, lengthy, intent consideration
	a remark expressing careful consideration
	expression without words
	the phenomenon of a propagating wave (light or sound) being thrown back from a surface