Either solid (if it also has a definite shape) or liquid (if it doesn't).
Solid.
A state of matter having definite volume but no definite shape is called, "liquid".
a liquid
liquid
The liquid phase
gaseous phase
Solids are the only phase of matter which have a fixed shape and volume.
gas
a solide has a shape of its shape and volume
a solide has a shape of its shape and volume
Gas
That's a "gas" (or a plasma).