Meaning

verb be undecided about something; waver between conflicting positions or courses of action

verb move or swing from side to side regularly

originFirst attested in 1726; borrowed from Latin ōscillātus, perfect passive participle of Latin ōscillō (“to swing”) (see -ate (verb-forming suffix)), from ōscillum (“a swing”), usually identified with ōscillum (“a little face or mask hung on a tree that sways with the wind”), diminutive of ōs (“mouth, face”). See also osculate.

Etymology from Wiktionary, CC BY-SA 3.0