What does the term 'chromatic' refer to in music?

The term 'chromatic' in music primarily refers to the presence of all half steps within an octave. This concept arises from the chromatic scale, which includes all twelve pitches available in Western music, represented by both the white and black keys on a piano. Each successive note in the chromatic scale is a half step apart, showcasing the complete range of available pitches, as opposed to major or minor scales, which consist of specific whole and half step patterns.

The chromatic scale illustrates how half steps are integral to the construction of melodies and harmonies. By incorporating these half steps, composers can create tension and color in their music, leading to more complex and engaging musical phrases. This contrasts with other options, which do not accurately capture the essence of what 'chromatic' implies in a musical context.