single out vs tell

single out and tell both are verbs.

Word	Noun	Adjective	Verb	Adverb
single out	No	No	Yes	No
tell	No	No	Yes	No

As verbs, tell is a hypernym of single out; that is, tell is a word with a broader meaning than single out:

Other hypernyms of single out include differentiate, distinguish, secern, secernate, separate, severalise, severalize, tell apart.

single out (verb)	tell (verb)
select from a group	discern or comprehend
treat differently on the basis of sex or race	mark as different
	let something be known
	narrate or give a detailed account of
	give instructions to or direct somebody to do something with authority
	give evidence
	express in words
	inform positively and with certainty and confidence