The Collaborative International Dictionary of English v.0.48:

nonstop \nonstop\ adj.
   1. without an intermediate stop; -- of trips in public
      conveyances, especially of a flight.
      [WordNet 1.5]

   2. same as around-the-clock.

   Syn: around-the-clock, day-and-night, round-the-clock.
        [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

nonstop \nonstop\ n.
   A flight made without intermediate landings between source
   and destination; as, how many nonstops are there to Dallas?.

   Syn: nonstop flight.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

nonstop
    adv 1: without stopping; "we are flying nonstop form New York to
           Tokyo"
    adj 1: (of a journey especially a flight) occurring without
           stops; "a nonstop flight to Atlanta"
    2: at all times; "around-the-clock nursing care" [syn: around-
       the-clock, day-and-night, nonstop, round-the-clock]
    n 1: a flight made without intermediate stops between source and
         destination; "how many nonstops are there to Dallas?" [syn:
         nonstop flight, nonstop]