counterpoint

v. combine one melody with another (Music)

n. combining of two melodies into one harmonic texture (Music)

In music, counterpoint is the relationship between two or more voices that are independent in contour and rhythm, and interdependent in harmony. It has most commonly been identified in Western music, developing strongly in the Renaissance, and also dominant in much of the common practice period, especially in Baroque music. The term comes from the Latin punctum contra punctum ("note against note"). The adjectival form contrapuntal shows this Latin source more transparently.
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(n.)
The setting of note against note in harmony; the adding of one or more parts to a given canto fermo or melody
  

(n.)
The art of polyphony, or composite melody, i. e., melody not single, but moving attended by one or more related melodies.
  

(n.)
Music in parts; part writing; harmony; polyphonic music. See Polyphony.
  

(n.)
An opposite point
  

(n.)
A coverlet; a cover for a bed, often stitched or broken into squares; a counterpane. See 1st Counterpane.
  

Noun
1. a musical form involving the simultaneous sound of two or more melodies
(hypernym) polyphony, polyphonic music, concerted music
(class) inversion
Verb
1. to show differences when compared; be different; "the students contrast considerably in their artistic abilities"
(synonym) contrast
(hypernym) differ
(hyponym) oppose, counterbalance
2. write in counterpoint; "Bach perfected the art of counterpointing"
(hypernym) compose, write
(classification) music