fidelity to one's lord; the feudal obligation by which the tenant or vassal was bound to be faithful to his lord; the special oath by which this obligation was assumed; fidelity to a superior power, or to a government; loyality. it is no longer the practice to exact the performance of fealty, as a feudal obligation.-fidelity; constancy; faithfulness, as of a friend to a friend, or of a wife to her husband.