espouse: [15] Etymologically, to espouse something is the same as to sponsor it. Both words go back ultimately to Latin spondēre ‘promise solemnly’. From it developed late Latin spōnsāre, which produced Old French espouser, source of the English verb. It originally meant ‘promise to marry’, but this particular semantic strand has survived only in the related noun spouse, and by the 17th century the now familiar metaphorical sense ‘adopt and support a cause’ had developed. => sponsor, spouse[espouse etymology, espouse origin, 英语词源]