BY STEALTH
Meaning of BY STEALTH in English
adverb
Synonyms: secretly , clandestinely, covertly, furtively, hugger-mugger, in camera, privately, stealthily, sub rosa, surreptitiously
Merriam Webster.
Collegiate thesaurus English vocabulary.
Английский энциклопедический словарь тезаурус.
2003