2H or 2-H may refer to:
Chemistry Deuterium, or , an isotope of hydrogen 2H, a designation for chemicals with two hydrogen molecules 2H-pyran, a form of Pyran 2H-1-benzopyran, a form of Benzopyran 2H-pyran-2-one, a form of 2-Pyrone
Transport 2H, a type of Toyota H engine 2H, a type of Volkswagen EA827 engine Douglas O-2H, a model of Douglas O-2 Chaparral 2H, a model of Chaparral Cars Aptera 2h, a model in the Aptera 2 Series SSH 2H (WA), alternate designation for Washington State Route 290
Other uses 5days half of a fiscal year 2H, a harder grade of pencil lead
See also H2 (disambiguation)