The Collaborative International Dictionary
debilitative
debilitative \debilitative\ adj. causing weakness. [Narrower terms: debilitating (vs. invigorating)]
Syn: enervating, enfeebling, weakening.
WordNet
debilitative
adj. causing debilitation [syn: enervating, enfeebling, weakening]
Usage examples of "debilitative".
Although he knew that Commander Grace’s modifications to the deflector shields protected the ship’s dilithium crystals from the region’s debilitative effects, it was still comforting to be back in normal space.