at the least vs at least

at the least and at least both are adverbs.

Word	Noun	Adjective	Verb	Adverb
at the least	No	No	No	Yes
at least	No	No	No	Yes

As adverbs, at the least and at least are synonyms defined as:

at the least (adverb)	at least (adverb)
not less than	not less than
	if nothing else (`leastwise' is informal and `leastways' is colloquial)