companion

from The Century Dictionary.

• To be a companion to; accompany.
• To make equal; put on the same level.
• noun One who accompanies or associates with another, either habitually or casually; one who shares the lot of another; a mate; a comrade.
• noun A fellow; a worthless person.
• noun One who holds the lowest rank in an English honorary order: as, a companion of the Bath (abbreviated C. B.), St. Michael and St. George, etc.
• To associate or keep company: used with with: as, to companion with vagabonds.
• noun Nautical: The framing and sash-lights on the quarter-deck or round-house, through which light passes to the cabins and deck below.
• noun A raised hatch or cover to the cabin-stair of a merchant vessel.
• A simplified spelling of companion.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb rare To be a companion to; to attend on; to accompany.
• transitive verb obsolete To qualify as a companion; to make equal.
• noun One who accompanies or is in company with another for a longer or shorter period, either from choice or casually; one who is much in the company of, or is associated with, another or others; an associate; a comrade; a consort; a partner.
• noun A knight of the lowest rank in certain orders.
• noun obsolete A fellow; -- in contempt.
• noun A skylight on an upper deck with frames and sashes of various shapes, to admit light to a cabin or lower deck.
• noun A wooden hood or penthouse covering the companion way; a companion hatch.
• noun (Naut.) a wooden porch over the entrance or staircase of the cabin.
• noun (Naut.) the ladder by which officers ascend to, or descend from, the quarter-deck.
• noun (Naut.) a staircase leading to the cabin.
• noun in certain honorary orders, the members of the lowest grades as distinguished from knights commanders, knights grand cross, and the like.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A friend, acquaintance, or partner; someone with whom one spends time or keeps company
• noun dated A person employed to accompany or travel with another.
• noun nautical The framework on the quarterdeck of a sailing ship through which daylight entered the cabins below.
• noun nautical The covering of a hatchway on an upper deck which leads to the companionway; the stairs themselves.
• noun topology A knot in whose neighborhood another, specified knot meets every meridian disk.
• noun figuratively A thing or phenomenon that is closely associated with another thing, phenomenon, or person.
• noun astronomy A celestial object that is associated with another.
• verb obsolete To be a companion to; to attend on; to accompany.
• verb obsolete To qualify as a companion; to make equal.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun one paid to accompany or assist or live with another
• verb be a companion to somebody
• noun a traveler who accompanies you
• noun a friend who is frequently in the company of another