Words, grammatical forms and meanings linked to the ontology.
3H en · NOUN
Meanings
(British, English, uncountable, usually) A grade of pencil with lead that makes lighter marks than a pencil grade 2H but darker marks than a pencil of grade 4H; a pencil with hard lead.
(uncountable, usually) A pencil of grade 3H.
(uncountable, usually) tritium. In this case, the "3" should be superscripted: ³H.