Vaguely means in an unclear fuzzy way, or only slightly. Vaguely familiar, vaguely remember, vaguely aware.
Before an adjective it is a hedge meaning slightly and no more — vaguely interested, vaguely Italian — and it is one of the most useful words in English for damning with faint description. With a verb of knowing it means imprecisely: I vaguely remember. Note vague, vagueness; and that the Latin behind it means wandering, which is what a vague idea does.
1adverbvaguelyIn an unclear fuzzy way.
“I vaguely remember meeting him at a party years ago.”
2adverbslightlyOnly slightly.
“I felt vaguely uneasy about the plan, though I couldn't say why.”
vaguely is a manner of imprecision.
Latin
vagus — uncertain, vague
Middle French
vague
English
vague
English, today
vaguely
From vague + -ly. vague comes from Middle French vague, from Latin vagus (“uncertain, vague”) literally “wandering, rambling, strolling”.
Etymology from Wiktionary, CC BY-SA