Glossary of Terms:
 
note number
Most commonly referred to as MIDI note number. In MIDI data, each note is assigned a MIDI note number and a MIDI channel, in order to keep it seperate from other notes on other MIDI channels. When using a MIDI sequencer, this number makes it easy to find and edit a specific note (or notes) for a specific sound used in the song.
Source: Yamaha

Related terms:
  MIDI   program change   sequencer