wage

Wage comes from Middle English wage, from Anglo-Norman and Old Northern French wage, a variant of Old French gauge/guage, from Medieval Latin wadium, from Frankish *waddī, meaning 'pledge.' That root traces further to Proto-Germanic *wadją and Proto-Indo-European *wedʰ-, 'to pledge, redeem a pledge.'

The verb form, wagen, meant simply 'to pledge' in Middle English, coming through the same Old Northern French line as wagier. Over time the pledge narrowed to a specific kind: the money promised for labor.

Wage is a doublet of gage, both descending from the same Old French root, one via the northern dialect, one via the standard form. It's also 'more at wed' — connected through Old English wedd and the same Proto-Germanic *wadją.