close to vs roughly

close to and roughly both are adverbs.

Word	Noun	Adjective	Verb	Adverb
close to	No	No	No	Yes
roughly	No	No	No	Yes

As adverbs, close to and roughly are synonyms defined as:

close to and roughly: (of quantities) imprecise but fairly close to correct

Other synonyms of close to include about, approximately, around, just about, more or less, or so, some.

close to (adverb)	roughly (adverb)
(of quantities) imprecise but fairly close to correct	(of quantities) imprecise but fairly close to correct
	with rough motion as over a rough surface
	with roughness or violence (`rough' is an informal variant for `roughly')