The Collaborative International Dictionary of English v.0.48:
Nonacceptance \Non`ac*cept"ance\, n. A neglect or refusal to accept. [1913 Webster]WordNet (r) 3.0 (2006):
nonacceptance n 1: the act of refusing an offer; "the turndown was polite but very firm" [syn: nonacceptance, turndown]