vagabond (adj.) early 15c. (earlier vacabond, c. 1400), from Old French vagabond, vacabond "wandering, unsteady" (14c.), from Late Latin vagabundus "wandering, strolling about," from Latin vagari "wander" (from vagus "wandering, undecided;" see vague) + gerundive suffix -bundus.

also from early 15c. vagabond (n.)

c. 1400, earlier wagabund (in a criminal indictment from 1311); see vagabond (adj.). Despite the earliest use, in Middle English often merely "one who is without a settled home, a vagrant" but not necessarily in a bad sense. Notion of "idle, disreputable person" predominated from 17c.

also from c. 1400 Entries linking to vagabond vague (adj.) "uncertain as to specifics," 1540s, from French vague "empty, vacant; wild, uncultivated; wandering" (13c.), from Latin vagus "strolling, wandering, rambling," figuratively "vacillating, uncertain," perhaps from PIE *Huog-o- and cognate with Old Norse vakka "to stray, hover," Old High German wankon "to totter, stagger," Old High German winkan "to waver, stagger, wink," Old English wincian "to nod" [de Vaan]. Related: Vagueness.