a. - Next in order after the sixth;; coming after six others.
a. - Constituting or being one of seven equal parts into which anything is divided; as, the seventh part.
n. - One next in order after the sixth; one coming after six others.
n. - The quotient of a unit divided by seven; one of seven equal parts into which anything is divided.
n. - An interval embracing seven diatonic degrees of the scale.
n. - A chord which includes the interval of a seventh whether major, minor, or diminished.