promissory : Idioms & Phrases

• noun a promise to pay a specified amount on demand or at a certain time
  note; note of hand.
  
  • I had to co-sign his note at the bank

WordNet

• (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.

Webster 1913