Entries linking to stilly
Old English stille "motionless, stable, fixed, stationary," from Proto-Germanic *stilli- (source also of Old Frisian, Middle Low German, Middle Dutch stille, Dutch stil, Old High German stilli, German still), from PIE *stel-ni-, suffixed form of root *stel- "to put, stand, put in order," with derivatives referring to a standing object or place. Meaning "quiet, calm, gentle, silent" emerged in later Old English. Euphemistic for "dead" in stillborn, etc. Still small voice is from KJV:
And he said, Go forth, and stand upon the mount before the LORD. And, behold, the LORD passed by, and a great and strong wind rent the mountains, and brake in pieces the rocks before the LORD; but the LORD was not in the wind: and after the wind an earthquake; but the LORD was not in the earthquake: and after the earthquake a fire; but the LORD was not in the fire: and after the fire a still small voice. [I Kings xix.11-13]
Used as a conjunction from 1722.
common adverbial suffix, forming from adjectives adverbs signifying "in a manner denoted by" the adjective, Middle English, from Old English -lice, from Proto-Germanic *-liko- (cognates: Old Frisian -like, Old Saxon -liko, Dutch -lijk, Old High German -licho, German -lich, Old Norse -liga, Gothic -leiko); see -ly (1). Cognate with lich, and identical with like (adj.).
Weekley notes as "curious" that Germanic uses a word essentially meaning "body" for the adverbial formation, while Romanic uses one meaning "mind" (as in French constamment from Latin constanti mente). The modern English form emerged in late Middle English, probably from influence of Old Norse -liga.