e/Hasse invariant of a quadratic form

Information
has gloss	eng: In mathematics, the Hasse invariant (or Hasse–Witt invariant) of a quadratic form Q over a field K takes values in the Brauer group Br(K).The quadratic form Q may be taken as a diagonal form
lexicalization	eng: Hasse invariant of a quadratic form
instance of	e/Quadratic form