fold

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A fenced enclosure for livestock, especially sheep.
• noun A flock of sheep.
• noun A group of people or institutions bound together by common beliefs and aims.
• noun A religious congregation.
• transitive verb To place or keep (sheep, for example) in a fenced enclosure.
• intransitive verb To bend over or double up so that one part lies on another part.
• intransitive verb To make compact by doubling or bending over parts.
• intransitive verb To bring from an extended to a closed position.
• intransitive verb To bring from a compact to an extended position; unfold.
• intransitive verb To place together and intertwine.
• intransitive verb To envelop or clasp; enfold.
• intransitive verb To blend (a light ingredient) into a heavier mixture with a series of gentle turns.
• intransitive verb Informal To discontinue operating; close.
• intransitive verb Games To withdraw (one's hand) in defeat, as by laying cards face down on a table.
• intransitive verb Geology To form bends in (a stratum of rock).
• intransitive verb To become folded.
• intransitive verb To be capable of being folded.
• intransitive verb Informal To close, especially for lack of financial success; fail.
• intransitive verb Games To withdraw from a game in defeat.
• intransitive verb To give in; buckle.
• intransitive verb To weaken or collapse from exertion.
• noun The act or an instance of folding.
• noun A part that has been folded over or against another.
• noun A line or mark made by folding; a crease.
• noun A coil or bend, as of rope.
• noun Chiefly British A hill or dale in undulating country.
• noun Geology A bend in a stratum of rock.
• noun Anatomy A crease or ridge apparently formed by folding, as of a membrane; a plica.

from The Century Dictionary.

• To double over upon itself; lay or bring one part of over or toward another by bending; bend over: used of things thin and flexible, or relatively so, as a piece of cloth, a sheet of paper, a stratum of rock, etc.: often with up.
• To bring together or place over each other, as two correlated parts: as, to fold together the ends of a piece of cloth; to fold one's arms or one's hands.
• To inclose in a fold or in folds; wrap up; cover up or hide away.
• To inclose in or as in the arms; embrace.
• To throw down; overthrow; cause to yield.
• To become doubled upon itself; become bent so that one part lies over upon another.
• To infold; embrace.
• To yield; give way; fail.
• noun A double or bend in a more or less flexible substance, as cloth; a flexure, especially one so extensive as to bring the parts on either side of the line of bending near together.
• noun The parts which are brought together by bending or folding, or one of them; specifically, a plait in a garment or in drapery: as, a broad fold of cloth.
• noun In entomology, a plica or ridge, generally inclined to one side, appearing as if the surface had been folded.
• noun plural Involved parts of a complex whole; windings: a complex arrangement or constitution; intricacy.
• noun A clasp; an embrace.
• noun A sheaf or bundle, as of straw.
• noun See the adjectives.
• To confine, as sheep, in a fold.
• To confine sheep in a fold.
• noun A place of protection or inclosure for domestic animals, usually for sheep.