"Stealingly" is an adverb that means "in a manner of taking something without permission." The word is spelled /ˈsti.lɪŋ.li/ in IPA phonetic transcription. It is formed by adding the -ly suffix to the verb "stealing," which means to take something unlawfully. The pronunciation of "stealingly" is like "stee-ling-lee," with the primary stress on the second syllable. Though not commonly used, "stealingly" is a legitimate adverb in English language and is listed in most dictionaries.
The word "stealingly" is derived from the verb "steal". The "ly" suffix is added to the adjective form of "stealing", which means "done in a secret or surreptitious manner". The etymology of "steal" can be traced back to the Old English word "stelan", which has Germanic origins.