chordo-, chord-, cordo-, cord- +

(Greek: khorde, "gut string" [of a lyre]; used in an extended sense to mean "sinew, flexible rod-shaped organ, string, cord"; Latin: chorda, "related notes in music, string of a musical instrument, cat-gut" via Old French, corde, "rope, string, twist, cord")

rheochord
A metallic wire used for regulating the resistance of a circuit, or varying the strength of an electric current, by inserting a greater or less length of it into the circuit.
tetrachord
1. The basis of a variety of ancient musical scales, consisting of four notes, with an interval of a perfect fourth between the highest and lowest notes.
2. A group of four musical notes, the first and last of which form a perfect fourth, used principally in ancient Greek music.
tetrachordal
A reference to any of several groups of four notes in descending order, in which the first and last notes form a perfect fourth in musical theory; especially, of classical Greece.
tympanichord, chorda tympani
1. A derivative of the nervus intermedius (root of the facial nerve) which leaves the main nerve in the facial canal to enter the middle ear cavity.
2. A nerve given off from the facial nerve in the facial canal which passes through the posterior canaliculus of the chorda tympani into the tympanic cavity, crosses over the tympanic membrane and handle of the malleus, and passes out through the anterior canaliculus of the chorda tympani in the petrotympanic fissure to join the lingual branch of the mandibular nerve in the infratemporal fossa.

It conveys taste sensation from the anterior two-thirds of the tongue and carries parasympathetic preganglionic fibers to the submandibular ganglion, for innervation of the submandibular and sublingual salivary glands.

urochord
1. A flexible skeletal rod notochord that supports the posterior part of the body in some sea animals such as sea squirts.
2. The notochord (flexible rodlike structure) of an ascidian (marine animal with a saclike body and siphons through which water enters and leaves) or tunicate (marine animal with a saclike body), more conspicuous in the larva than in the adult and confined primarily to the caudal (tail or hind) region of the body.
urochordata
Tunicates which are marine, filter-feeding, creatures.

The most prominent tunicates are the sea squirts, which show affinities to other chordates only in the juvenile stage.

Adult sea squirts are sessile (attached), globular or tubular animals, often with prominent incurrent and excurrent siphons; many kinds of which grow in colonies.