A liquid has a definite volume (which can change with temperature), but takes the shape of its container.
A Liquid is the state that has no definite shape, since the atoms can move around, it is therefore able to form itself to the shape of its container. However, since the atoms still have weak bonds to one another, it cannot fill up a closed container by stretching out the atoms. (The form of matter that does this is a gas.)
* Liquids can be very slightly compressed, but not to the extent of gases. ---
There are 3 phases of matter. Solids, liquids and gases. Solids have a definite shape and a definite volume. Liquids do not have a definite shape but do have a definite volume. Gases do not have a definite shape as they can "flow", and they do not have a definite volume as they can fill a container by changing in pressure (density).
