Definition of third-party
(Entry 1 of 2)
1
: of, relating to, or involving a third party
third-party insurance
2
: of, relating to, or being software that is created by a vendor to be compatible with the products of another vendor
third party
nounDefinition of third party (Entry 2 of 2)
1
: a person other than the principals
a third party to a divorce proceeding insurance against injury to third parties
2a
: a major political party operating over a limited period of time in addition to two other major parties in a nation or state normally characterized by a two-party system
b
: minor party
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Merriam-Webster unabridged
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Time Traveler for third-party
The first known use of third-party was in 1641
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