Perneo, pernes, pernéui, pernêtum, pernêre, penul. prod. Mart. To spinne out the threede to the ende.
Lewis and Short: Latin dictionary
per-nĕo, nēvi, nētum, 2, v. a., to spin out, spin to an end, poet. of the Fates: cum mihi supremos Lachesis perneverit annos, Mart. 1, 89, 9; Sid. Carm. 15, 167.