subsidiary

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

• adjective Serving to assist or supplement; auxiliary.
• adjective Secondary in importance; subordinate.
• adjective Of, relating to, or of the nature of a subsidy.
• noun One that is subsidiary to another.
• noun A subsidiary company.
• noun Music A theme subordinate to a main theme or subject.

from The Century Dictionary.

• Held ready to furnish assistance; held as a reserve.
• Lending assistance; aiding; assistant; furnishing help; ancillary.
• Furnishingsupplementary supplies: as, a subsidiary stream.
• Relating or pertaining to a subsidy; founded on or connected with a subsidy or subsidies: as, a subsidiary treaty.
• noun One who or that which contributes aid or additional supplies; an auxiliary; an assistant.
• noun In music, a subordinate theme or subject, especially in an episode of an extended work.

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

• noun One who, or that which, contributes aid or additional supplies; an assistant; an auxiliary.
• adjective Furnishing aid; assisting; auxiliary; helping; tributary; especially, aiding in an inferior position or capacity.
• adjective Of or pertaining to a subsidy; constituting a subsidy; being a part of, or of the nature of, a subsidy.

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

• adjective auxiliary or supplemental
• adjective secondary or subordinate
• adjective of, or relating to a subsidy
• noun A company owned by the parent company or holding company
• noun music a subordinate theme

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

• adjective functioning in a supporting capacity
• noun a company that is completely controlled by another company
• noun an assistant subject to the authority or control of another