surreptitious

/səɹɪptˈɪʃəs/

/ˌsɝəpˈtɪʃəs/

surreptitious

doing something secretly in an attempt to avoid notice

synonyms : furtive

conducted with or marked by hidden aims or methods

Examples

1. Surreptitious astroturf methods are now more important to these interests than traditional lobbying of Congress.

2. It was more surreptitious than that.

3. Is there some kind of surreptitious radio signal passing between them.

4. So Sir Randolph Quirk today would have one foot in person for the surreptitious recording which he used to obtain data for the London-Lund corpus.