In a nonharmonic tone, preparation is, in the move of a pitch

Pitch (music)

Pitch is an auditory perceptual property that allows the ordering of sounds on a frequency-related scale.Pitches are compared as "higher" and "lower" in the sense associated with musical melodies,...

 or chord

Chord (music)

A chord in music is any harmonic set of two–three or more notes that is heard as if sounding simultaneously. These need not actually be played together: arpeggios and broken chords may for many practical and theoretical purposes be understood as chords...

 from a consonance

Consonance and dissonance

In music, a consonance is a harmony, chord, or interval considered stable, as opposed to a dissonance , which is considered to be unstable...

 to a dissonance, the consonant pitch or chord which precedes the dissonance. The move from the dissonance to a consonance is resolution

Resolution (music)

Resolution in western tonal music theory is the move of a note or chord from dissonance to a consonance .Dissonance, resolution, and suspense can be used to create musical interest...

.

For example, in the following anticipation, the preparation is on the left, the nonharmonic tone is in the center marked in red, and the resolution is on the right: