Is there a "quarter" equivalent for something divided in 9 pieces?

Something is divided in four pieces. One piece is called a fourth or a quarter.

Something is divided in nine pieces. One is piece is called a ninth or a... What is the 'quarter' equivalent for something divided by nine?


OED has a definition for...

ninth part n. each of the nine equal parts into which a thing may be divided; (also fig.) denoting a worthless or inadequate object or person, esp. in ninth part of a man.

Other than that the only word I know is pretty specific - it only applies to each of a 9-baby birth...

nonuplet (defn 2.) Each of nine siblings resulting from a single pregnancy. Usu. in pl.

Apparently there's only one in the world (only two sets are known, and all the other babies died).


I realize I'm very late to this, but I just did a crossword puzzle and the answer to the clue "many a pizza slice" was "octant".

I find this definition via google:

  1. an arc of a circle equal to one eighth of its circumference, or the area enclosed by such an arc with two radii of the circle. [Note: this justifies the pizza slice answer.]
  2. each of eight parts into which a space or solid body is divided by three planes that intersect (especially at right angles) at a single point.

H