Meaning of J in English

J

I. J 1 BrE AmE , j /dʒeɪ/ noun ( plural J’s , j’s ) [uncountable and countable]

the tenth letter of the English alphabet

II. J 2 BrE AmE

the written abbreviation of joule or joules

Longman Dictionary of Contemporary English.      Longman - Словарь современного английского языка.