It depends on what you mean by 'domestic partner': if by this you mean you are in a stable unmarried heterosexual relationship, then "you must be able to show that you are in a durable relationship with each other" (taken from: UK Border Agency | EEA family permits)
If however by 'domestic partner' you mean you are in a same-sex relationship which has been registered with the relevant authority (which is what is known as 'civil partnership' in the UK), then yes, it is recognised by the UKBA (see link above).
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