United StatesUnited KingdomGlobalformallegalneutral
To be involved in, privy to, or a participant in an action, agreement, or transaction; often used to indicate complicity or joint responsibility ('to be a party to' something).
2.
United StatesUnited KingdomGlobalinformalneutral
As part of the phrase 'give/throw a party to [someone]', to host or hold a social gathering for a person or group (construction: 'give a party to').