DOHC

Double Overhead Cam
Found on http://www3.sympatico.ca/dhaughey/j1930.htm

DOHC

Double Overhead Camshaft: a DOHC engine has two camshafts in each cylinder head; one camshaft operates the intake valves, the other actuates the exhaust valves.
Found on http://www.caranddriver.com/reviews/glossary-of-terms-info

DOHC

Dual Over Head Cams. Two camshafts found in the head or top of the engine that open and close the valves. Two cams allow more precise control than one.
Found on http://www.encyclo.co.uk/local/22062
No exact match found