What does DHO stand for?

Castle Boats Manufacturing, Harwood Heights, IL - Manufacturer code for watercraft hull identification number (USCG)

Damped Harmonic Oscillator - Electronics (ODA)

Department of Highways, Ontario (SAUS)

Deuterium Hydrogen - Protium Oxide - Organic chemistry (DAVI)

Dhodia - Language code (ETLW)

Dihydroouabain - Biochemistry

Director of Home Operations - Air Ministry - British - World War II

District Historical Office - or Officer - Navy

Downhill Only Ski Club (SAUO)