Affiance is a related term of contract.
In lang=en terms the difference between affiance and contract
is that
affiance is to be betrothed to; to promise to marry while
contract is to gain or acquire (an illness).
As verbs the difference between affiance and contract
is that
affiance is to be betrothed to; to promise to marry while
contract is (ambitransitive) to draw together or nearer; to shorten, narrow, or lessen.
As nouns the difference between affiance and contract
is that
affiance is faith, trust while
contract is an agreement between two or more parties, to perform a specific job or work order, often temporary or of fixed duration and usually governed by a written agreement.
As an adjective contract is
(obsolete) contracted; affianced; betrothed.