The story
From imperceptible + -ly.
Etymology from Wiktionary, CC BY-SA 4.0.
imperceptibly
Today it means: Not noticeably; such that it cannot be detected, through being too small or too fast, etc. Full definition →
Today it means: Not noticeably; such that it cannot be detected, through being too small or too fast, etc. Full definition →
From imperceptible + -ly.
Etymology from Wiktionary, CC BY-SA 4.0.