>>3Torah doesn't define "wife", as "wife" is a middle-high-german word and the Torah was written before this language evolved. Wife, in middle-high-german, simply means "woman".
In the Torah, there is no "wife" as the english understand it. Nor is there a "husband", as the english understand it. There is a man, who is the ba'al (master, lord, power), who owns females: be they adult or little girls. And he has sex with them.