There are two words here, though their spellings are easily
confused. The word for a rope or thick
string is spelled cord, while the
musical term describing the simultaneous combination of notes is spelled chord.
This may seem quite straightforward and uncontroversial, but it’s
interesting to observe that this distribution of the two spellings is
unetymological. The word we now spell cord is a borrowing of the French word corde, ‘string, rope’, which itself is
derived from the Latin chorda. It is first recorded in English in the 15th
century in the spelling cord;
however, in the 16th century it was respelled chord to reflect its Latin origins.
This spelling remained common in the 17th and 18th
centuries; it has survived into modern usage in certain specialised senses,
such as ‘that touched a chord’, and in the name of the musical instrument harpsichord.
Despite
its spelling, the musical term chord
is unrelated to Latin chorda; it
derives from accord in the sense ‘bring
into harmony’.The musical term first
appeared in English in the 15th century, when it was spelled corde; this word survives in the
spelling of accordion. In the 16th century it was
confused with the word corde,
‘string, rope’, and subjected to the same change in spelling, giving us the
word chord. So, while the spelling of these two words
might appear straightforward, their histories show that the spellings are,
etymologically-speaking, the wrong way round.
Chord should refer to the
rope, and the musical term should be cord. While this confusing history may appear to
have been straightened out in today’s usage, it has left some vestiges of
uncertainty. Should it be ‘vocal chords’
or ‘vocal cords’ for instance? The usual
spelling today is vocal cords, but
it’s common to find vocal chord. This is frequently stigmatised as a
folk-etymological spelling, implying confusion with the musical sense of chord, but it’s actually a genuine
survivor of the older spelling, first recorded in the 18th century.