Matters of Ear
Pulse: The unit of movement in music, one of a series of regularly recurring throbs or impulses.
Measure: A group of pulses.
Pulse-Group: Two or more tones grouped within the pulse.
Matters of Eye
Beat: One of a series of conventional movements made by the conductor. This might include any unconventional motion which served to mark the movement of the music, whether made by conductor, performer or auditor.
Beat-Note: A note of the denomination indicated by the measure-sign as the unit of note-value in a given measure.
Example
Given the following measure-signs: 2-4, 2-2, 2-8, quarter, half, or eighth notes, respectively, are beat-notes.
Beat-Group: A group of notes or notes and rests, of smaller denomination than the beat-note which represents a full beat from beginning to end and is equal in value to the beat-note. (A beat-group may begin with a rest.)