Definition of subreptitiously in US English:

subreptitiously

adverb

  • In a subreptitious manner; by subreption; = "surreptitiously" b.

Origin

Early 17th century; earliest use found in Randle Cotgrave (fl. 1587–?1630), lexicographer. From subreptitious + -ly, originally after French † subreptivement stealthily.

Pronunciation

subreptitiously

/ˌsʌbrɪpˈtɪʃəsli/