reaching vs attainment

reaching and attainment both are nouns.

Word	Noun	Adjective	Verb	Adverb
reaching	Yes	No	No	No
attainment	Yes	No	No	No

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

Other hyponyms of reaching include advent, coming.

reaching (noun)	attainment (noun)
accomplishment of an objective	the act of achieving an aim
the act of physically reaching or thrusting out	arrival at a new stage
	an ability that has been acquired by training