Adjectives

(a)likelyhas a good chance of being the case or of coming about“these services are likely to be available to us all before long”, “she is likely to forget”, “a likely place for a restaurant”, “the broken limb is likely to fall”, “rain is likely”, “a likely topic for investigation”, “likely candidates for the job”
(s)likely, potentialexpected to become or be; in prospect“potential clients”
(s)likelywithin the realm of credibility“not a very likely excuse”

Adverbs

(r)probably, likely, in all likelihood, in all probability, belikewith considerable certainty; without much doubt“He is probably out of the country”, “in all likelihood we are headed for war”