harmonize

verb

2.
write a harmony for
Derived from:
harmonization
Exemplifies:
American spelling
3.
sing or play in harmony
Exemplifies:
American spelling
4.
bring (several things) into consonance or relate harmoniously
Exemplifies:
American spelling
5.
bring into consonance or accord
Exemplifies:
American spelling
6.
bring into consonance, harmony, or accord while making music or singing
Derived from:
harmonization
Exemplifies:
American spelling