These words mean to be unwilling to accept, receive or take into account a person or thing. Reject is to fail to accept or grant, and caries overtones of casting aside as useless, value less or unsuitable.

• The judge rejected the prisoner’s appeal for a new trial; The idea that the earth is flat was rejected centuries ago.

Refuse and decline both mean to fail to comply with or to do something. Refuse is the stronger of the two words, often stressing firmness and sometimes even rudeness: to refuse to obey an order. It also suggests the idea of withholding: to refuse money to a beggar; to refuse to discuss the proposition. Decline , on the other hand, is to refuse politely and is applicable to invitations to social events, or to a courteous offer of help: to decline an invitation to a dinner party; a blind man who smilingly declined to be helped across the street. Decline may be used in place of refuse when an atmosphere of formality prevails: The witness declined to answer certain questions put to him. Knock back is a very informal substitute for refuse in contexts where something if offered; she knocked back his proposal.

Repudiate and spurn emphasize more pointedly than the foregoing words a refusal to recognize or have anything to do with a person or thing. Repudiate (which once meant to cast off or divorce a wife) points to a disowning or rejection of something once held more or less dear: to repudiate one’s religious beliefs; an author who repudiates the revolutionary ideas expressed in his earlier work; to repudiate one’s relatives because of their critical attitude. Derived from an Old English word meaning to kick out , spurn emphasizes even more strongly the idea of driving or pushing away roughly and contemptuously: spurning the attentions of a man whom she despised; spurning the suggestion that he should get his hair cut and put on a clean shirt; spurning a door-to-door salesman.