The E dominant seventh flat five chord (abbreviated "E7(b5) chord") is a four-note chord consisting of the notes E, G♯, B♭, and D. The chord is formed by lowering the fifth of a E dominant seventh chord a half step.
E dominant seventh flat five chord
E G♯ B♭ D
1 3 ♭5 ♭7
tetrad (four-note chord)