[nonce] n [ME nanes, alter. (fr. misdivision of then anes in such phrases as to then anes for the one purpose) of anes one purpose, irreg. fr. an, on one--more at one] (13c) 1: the one, particular, or present occasion, purpose, or use "for the ~"
2: the time being
[2]nonce adj (1884): occurring, used, or made only once or for a special occasion "a ~ word"