The shell of a clam. / A dredging bucket with hinges like the shell of a clam. / In food service, the closing box (usually styrofoam but sometimes cardboard) given to consumers with take-out food.

(manufacturing) To deform a die in a shape resembling the shell of a clam, as a result of uneven extrusion pressure. / To dig out by means of a clamshell (dredging bucket).

Done or kept in secret, sometimes to conceal an illicit or improper purpose. / (Freemasonry, of a person or lodge) Not recognized as a regular member.

Belonging to the best or top group in a system of classification. / Of, or relating to the most luxurious and expensive class of accommodation on a train, ship, hotel, etc.

(A status, section, etc which is of) premier rank. / (Ireland) the third year of primary school, following after the junior and senior infant levels.

(chiefly BDSM) A metal clamp, usually joined to another by a chain, meant to be worn on the nipples to cause pain.

Empty verbiage or nonsense. / (historical) A device for producing a clapping sound in theaters. / A device or trick to gain applause; a humbug.

(military) A cruiser equipped with sophisticated defenses against missile and air attack.

(of liquids, such as wine or syrup) To make clear or bright by freeing from feculent matter. / To make clear or easily understood; to explain in order to remove doubt or obscurity.

(music) A woodwind musical instrument that has a distinctive liquid tone whose characteristics vary among its three registers: chalumeau (low), clarion (medium), and altissimo (high).