The synonym of ''Stipulation'' is -

Stipulation (Noun)
English Meaning: A condition or requirement that is specified or demanded as part of an agreement.
Bangla Meaning: শর্তাধীন বিষয়
Synonym: condition, precondition, proviso, provision, prerequisite, requisite, specification
Example Sentence: They donated their collection of prints with the stipulation that they never be publicly exhibited.
 
Source: Oxford Dictionary, Bangla Academy Dictionary