The definition of a pledge is something held as security on a contract, a promise, or a person who is in a trial period before joining an organization.
(noun)Pledge is defined as to give something as security for a loan, promise, make an agreement, or accept a potential membership.
(verb)See pledge in Webster's New World College Dictionary
noun
Origin: ME plegge < OFr pleige < ML plegium < plevium, security, warranty, infl. by Frank *pligi, liability; akin to OS plegan, to warrant
transitive verb pledged, pledging
See pledge in American Heritage Dictionary 4
noun
Origin:
Origin: Middle English
Origin: , from Old French plege
Origin: , probably from Late Latin plevium, a security
Origin: , of Germanic origin; see dlegh- in Indo-European roots
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