slope vs gentleness

slope and gentleness both are nouns.

Word	Noun	Adjective	Verb	Adverb
slope	Yes	No	Yes	No
gentleness	Yes	No	No	No

As nouns, gentleness is a hyponym of slope; that is, gentleness is a word with a more specific, narrower meaning than slope:

slope: the property possessed by a line or surface that departs from the horizontal
gentleness: the property possessed by a slope that is very gradual

Other hyponyms of slope include grade, pitch, rake, slant, abruptness, precipitousness, steepness, gradualness.

slope (noun)	gentleness (noun)
the property possessed by a line or surface that departs from the horizontal	acting in a manner that is gentle and mild and even-tempered
an elevated geological formation	the property possessed by a slope that is very gradual

slope (verb)	gentleness (verb)
be at an angle