DIESIS

‖Di″e‐sis (?), n.; pl. Dieses (#). [[NL., fr. Gr. �, fr. � to let go through, dissolve; διά through + � to let go, send.]] 1. 1. (Mus.) A small interval, less than any in actual practice, but used in the mathematical calculation of intervals.
2. 2. (Print.) The mark †; — called also double dagger.