2H

2H (usually uncountable, plural 2Hs)

1. (British English) A grade of pencil with lead that makes lighter marks than a pencil grade H but darker marks than a pencil of grade 3H; a pencil with hard lead.
2. A pencil of grade 2H.
3. deuterium. In this case, the "2" should be superscripted: ²H.

• H2