adjective

surreptitious

sur-up-TISH-us/ˌsɜːrəpˈtɪʃəs/

Done secretly to avoid notice or disapproval.

The person takes a surreptitious cookie while checking whether the baker notices.

An adult at a family kitchen table secretly takes one cookie from a cooling tray while glancing sideways to check whether the nearby baker has noticed, one hand discreetly behind their back, playful mild disapproval context.
Etymology

“From under” contributes the idea of secrecy to “snatch,” producing a verb meaning “steal” or “seize secretly.” The adjective carries that furtive quality into actions done covertly or without legitimate authority.

In context

Allellu86:43
When he sold a work for an enormous price to one bookseller, even to Kramer, whom he really respected, he took care that a surreptitious edition should appear in Holland
Proofs of a Conspiracy [Part 1 of 2] by John Robison | Full Audiobook, Read-Along

More examples

  • He slips the dog a surreptitious snack under the table.
  • The students exchange surreptitious notes while the teacher writes.
  • The investigation uncovers surreptitious payments to a public official.

Forms

surreptitiously adverb — Secretly, to avoid being noticed or disapproved of.

Similar words

furtive
Often suggests nervous behavior or fear of being caught.
clandestine
Often describes organized activities kept secret because they are forbidden.
stealthy
Emphasizes quiet, careful movement intended to escape detection.