(n) a promise to pay a specified amount on demand or at a certain time, Syn. note of hand, promissory note, Example:I had to co-sign his note at the bank
The Collaborative International Dictionary of English (GCIDE) v.0.53 Collaborative International Dictionary (GCIDE)
a. Containing a promise or binding declaration of something to be done or forborne. [ 1913 Webster ]
Promissory note (Law), a written promise to pay to some person named, and at a time specified therein, or on demand, or at sight, a certain sum of money, absolutely and at all events; -- frequently called a note of hand. Kent. Byles. Story. [ 1913 Webster ]