negotiable instrument(n = noun.communication) - an unconditional order or promise to pay an amount of money;
is a kind of instrument, legal document, legal instrument, official document
has particulars: bill of exchange, draft, order of payment

beating-reed instrument, bowed stringed instrument, brass instrument, commercial instrument, debt instrument, derivative instrument, double-reed instrument, drafting instrument, electronic instrument, execution of instrument, free-reed instrument, instrument, instrument flying, instrument landing, instrument of execution, instrument of punishment, instrument of torture, instrument panel, legal instrument, measuring instrument, medical instrument, musical instrument, musical instrument digital interface, navigational instrument, negotiable, optical instrument, percussion instrument, percussive instrument, recording instrument, reed instrument, scientific instrument, sealed instrument, single-reed instrument, stringed instrument, surgical instrument, surveying instrument, surveyor's instrument, test instrument vehicle, time-delay measuring instrument, transit instrument, wind instrument, woodwind instrument