Incomplete /(?)/

In·com·plete

Incomplete

a.
  1. Not complete; not filled up; not finished; not having all its parts, or not having them all adjusted; imperfect; defective.
    A most imperfect and incomplete divine.
  2. Wanting any of the usual floral organs; -- said of a flower. (Bot.)

Phrases & Compounds
Incomplete equation
an equation some of whose terms are wanting; or one in which the coefficient of some one or more of the powers of the unknown quantity is equal to 0.