skyline vs lineation

skyline and lineation both are nouns.

Word	Noun	Adjective	Verb	Adverb
skyline	Yes	No	No	No
lineation	Yes	No	No	No

As nouns, lineation is a hypernym of skyline; that is, lineation is a word with a broader meaning than skyline:

Other hypernyms of skyline include outline.

skyline (noun)	lineation (noun)
the line at which the sky and Earth appear to meet	the act of marking or outlining with lines
the outline of objects seen against the sky	the line that appears to bound an object