Articulation: Indications to the performer about how a note should be played. Examples of articulation are legato and staccato.
Hertz: Cycle per second.
Legato: A manner of playing where the notes are connected and transitions between notes are smooth.
Monophonic: Only one note is being played at a time.
Octave: Musically, octaves are 12 half steps apart. When listening to two notes that are an octave apart, there is a strong sense that the notes are the same. In fact, musicians refer to notes that are an octave apart by the same letter. Physically, octaves are multiples of the fundamental frequency For example, A2 is at 110 Hz (the 2 denotes octave number). A3 is located at 220 Hz, and A4 is at 440 Hz.
Pitch:Musicians represent pitch by letter names, using the letters A-G and the ideas of "flat" and "sharp." Pitch is a perceptual phenomenon. Physically, pitch is represented by the frequency of the sound wave. For more information about the difference between the perception of pitch and the physical sound wave, check out The Psychology of Music, Diana Deutsch ed., second edition published in 1999 by Academic Press.
Staccato: A manner of playing where the notes are separated. Often the separation comes from drastically shortening the notes.
Timbre: Characteristic sound. Most often used to refer to the sound quality that allows one to distinguish between the same note played on different instruments. Also called Tone Color.
Vibrato: Small, rapid fluctuation of pitch. Vibrato is characteristic of the sound of some instruments, such as the violin or voice, while absent in the sound of other instruments, such as the piano.