The description of the telekinesis spell in the PHB states, under the "Object" section of the spell:
You can try to move an object that weighs up to 1,000 pounds.
You can exert fine control on objects with your telekinetic grip, such as manipulating a simple tool, opening a door or a container, stowing or retrieving an item from an open container, or pouring the contents from a vial.
For reference, the definition of "object" is:
- a material thing that can be seen and touched.
The answers to the question What is considered an object? seem to imply that any material that is inanimate is an object. However, the use of ‘object’ does not jibe well with what I typically consider to be an object, as I would say that an object needs to be discernible from its surroundings, something you can pick up and manipulate.
Is uncontained liquid (like a puddle of water) considered an object? Can it be controlled with telekinesis?