Discreetly

In a careful, quiet, and subtle way that avoids drawing attention or revealing secrets.

From French 'discret', derived from Latin 'discretus' meaning 'separated' or 'distinct', the past participle of 'discernere' meaning 'to separate' or 'to distinguish'. The 'ly' suffix makes it an adverb. Over time, it evolved to mean doing things in a separate, unobtrusive way.