Frieza was dead for fourteen years before being resurrected.
After his defeat at the hands of Future Trunks on Earth, Frieza's soul was sent to Earth's Hell. This wasn't the fiery, tormenting hell one might imagine; instead, Frieza was subjected to a saccharine and arguably more torturous experience. He spent fourteen years surrounded by angels and fairies, forced to relive his defeats at the hands of Goku and Trunks. This prolonged period of "punishment" ended when he was resurrected using the Dragon Balls by his surviving soldiers.
In summary, Frieza experienced fourteen years of afterlife before his return to the living world.
