UNLI'KELY, adjective 1. Improbably; such as cannot be reasonably expected; as an unlikely event. The thing you mention is very unlikely 2. Not promising success. He employs very unlikely means to effect his object. UNLI'KELY, adverb Improbably.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI