Step-Son
Defined in 2 dictionaries — Bouvier (1914), Black's (1910)
Bouvier's Law Dictionary and Concise Encyclopedia
John Bouvier; revised by Francis Rawle · 1914
The son of one’s wife by a former husband,' or of one’s husband by a former wife.
Black's Law Dictionary
Henry Campbell Black, M.A. · 1910
The sen of one's wife by a former husband or of one's husband by a former wife.