egoism - a) (phil.) the doctrine that we have proof of nothing but our own existence; egoism; b) (ethics) the doctrine that self-interest is the proper goal of all human actions (as opp. to altruism); egoism; c) the tendency to be self-cantered or to consider only oneself and one's own interests; egoism.

egoist - he who speaks only of himself or has excessive concern for his own interests; b) a man who advocates that we have proof of nothing but our own existence; c) a man who upholds the doctrine that self-interest is the proper goal of all human actions.