Draining
Part of speech: verb
Definition: To lose liquid.
Part of speech: noun
Definition: the practice of exploring drains, tunnels, or sewers
Part of speech: adjective
Definition: That drains
Example sentence: Being on the move all the time is draining, but the rewards make up for it.
Debilitating
Part of speech: adjective
Definition: Causing a loss of energy or strength.
Part of speech: verb
Definition: To make feeble; to weaken.
Example sentence: No sane man can afford to dispense with debilitating pleasures. No ascetic can be considered reliably sane.