¿Añadir también "acoplado, acoplada"?
gatecrasher n
figurative, informal (uninvited attendee)
colado, colada nm, nf
intruso, intrusa nm, nf
(CL: coloquial)
acoplado, acoplada nm, nf
I have a feeling that those two guys weren't invited to the wedding - they're gatecrashers...