• (in electrical engineering and electronics) the imaginary quantity equal to the square root of minus one.

  Compare with i

nounJs, J's

• 1The tenth letter of the alphabet.

  1. 1.1Denoting the next after I (or H if I is omitted) in a set of items, categories, etc.

• 2JA shape like that of a capital J.

• 3archaic Used instead of I as the Roman numeral for one in final position.

  More example sentences

  • ‘between ij and iij of the clock’

abbreviation

• 1Jack (used in describing play in card games).

• 2Physics
  Joule(s).

• 3(in titles) Journal (of)

  More example sentences

  • ‘J. Biol. Chem’

• 4Judge.

• 5Justice.