"Deny" involves a contradiction or rejection of an accusation or statement, while "refuse" is a straightforward decline. Denying implies a struggle against something, while refusing is a simple rejection. Denying is saying a statement is not valid, while refusing is rejecting an offer, request, order, or activity.

Both of them refer to negatively rejecting something/someone. However, 'deny' is used when we want to show that something is not valid, or does not exist. 'Refuse', contrariwise, points out that someone does not accept something/someone, but that thing/person exists.

Deny means declaring something untrue or refusing to acknowledge something while refusing means declining or rejecting something. Deny is used to deny an accusation or access to something, while refuse is used to refuse an offer or request.

“Reject” pertains to objects or proposals and signifies discarding something, “refuse” involves an active decision against something, signifying a personal choice to say “no,” “deny” is to reject the truth or validity, often related to refuting accusations, and “decline” is a polite refusal, saying “no” graciously.