contract

A contract is a legally binding exchange of promises or agreement between parties that the law will enforce. Contract law is based on the Latin phrase pacta sunt servanda (pacts must be kept). Breach of contract is recognised by the law and remedies can be provided. Almost everyone makes contracts every day. Sometimes written contracts are required, e.g., when buying a house. However the vast majority of contracts can be and are made orally, like buying a law text book, or a coffee at a shop. Contract law can be classified, as is habitual in civil law systems, as part of a general law of obligations (along with tort, unjust enrichment or restitution).
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n. contract, agreement; pact, treaty

(v. i.)
To make an agreement; to covenant; to agree; to bargain; as, to contract for carrying the mail.
  

(v. i.)
To be drawn together so as to be diminished in size or extent; to shrink; to be reduced in compass or in duration; as, iron contracts in cooling; a rope contracts when wet.
  

(n.)
To shorten by omitting a letter or letters or by reducing two or more vowels or syllables to one.
  

(n.)
To enter into, with mutual obligations; to make a bargain or covenant for.
  

(n.)
To draw together so as to wrinkle; to knit.
  

(n.)
To draw together or nearer; to reduce to a less compass; to shorten, narrow, or lessen; as, to contract one's sphere of action.
  

(n.)
To bring on; to incur; to acquire; as, to contract a habit; to contract a debt; to contract a disease.
  

(n.)
To betroth; to affiance.
  

(n.)
The agreement of two or more persons, upon a sufficient consideration or cause, to do, or to abstain from doing, some act; an agreement in which a party undertakes to do, or not to do, a particular thing; a formal bargain; a compact; an interchange of legal rights.
  

(n.)
The act of formally betrothing a man and woman.
  

(n.)
A formal writing which contains the agreement of parties, with the terms and conditions, and which serves as a proof of the obligation.
  

(a.)
Contracted; as, a contract verb.
  

(a.)
Contracted; affianced; betrothed.
  

A term of reference describing a unit of trading for a financial or commodity future. Also, the actual bilateral agreement between the buyer and seller of a transaction as defined by an exchange.