crico-, cric- +

(Greek: ring; used in the extended sense of pertaining to the [ring-shaped] cartilage that forms the back and lower part of the laryngeal cavity)

cricoid
1. Resembling a ring; referring especially to the cartilage at the larynx, and the adjoining parts.
2. Relating to, or in the region of, the lowermost cartilage of the larynx.
cricoidectomy
Excision of the cricoid cartilage.

The cricoid (from the Greek krikoeides, "ring-shaped") is the only complete ring of cartilage around the trachea which is a tube-like portion of the breathing or "respiratory" tract that connects the "voice box" (larynx) with the bronchial parts of the lungs.

cricopharyngeal
Relating to the cricoid cartilage and the pharynx; a part of the inferior constrictor muscle of the pharynx.
cricothyrotomy
Surgical incision through the skin and cricothyroid membrane for relief of respiratory obstruction; used prior to or in place of tracheotomy in certain emergency respiratory obstructions.
intercricothyrotomy
Surgical incision of the larynx through the lower part of the fibroelastic membrane of the larynx (cricothyroid membrane); inferior laryngotomy.