the word 'tomboy' emerged in the mid-16th century, originally used to refer to a boisterous or bold boy. by the late 16th century, its application shifted to describe a girl who behaves in a lively, boisterous manner like a boy. the name 'tom,' a common nickname for thomas, was long used generically to denote a male, as seen in terms like 'tomcat.' the addition of the old english adjectival suffix '-ish,' which denotes "having the character of," transforms the noun into an adjective. thus, 'tomboyish' literally means "having the character of a tomboy," describing qualities or behaviors culturally associated with boys but exhibited by a girl or woman.

Structure: tomboy + ish - tomboy: (english, compound noun) from the name 'tom' (a generic name for a male) + 'boy'. - ish: (old english, suffix) a suffix forming adjectives, meaning "having the qualities or characteristics of," "somewhat," or "approximately."