Anything which can occupy space and has some mass that can be perceived by senses like touch, see, smell, etc..,
Matter mainly exist in solid, liquid, and gaseous state
Solid-state
The molecules are closely packed so that the interparticle space is the least.
It has a definite shape and volume.
Example: ice.
Liquid state
The molecules are less closely packed compared to solid-state.
The inter-particle space is larger compared to the solid-state.
It has a definite volume (volume remains the same even if the container differs) but takes the shape of the container it occupies so no definite shape.
Example: water
Gaseous state
The molecules are loosely packed compared to liquid and solid-state.
The inter-particle space is the largest.
It has no definite shape and volume.
Example: water vapour.
Therefore, liquid has a definite volume but no definite shape