The phrase "putting to sleep" is one of the euphemisms we use to describe the act of euthanizing an animal. It is a practice that is employed for a variety of reasons, including releasing the animal from suffering due to illness, injury or old age. However, despite the usefulness of the term, there are instances when it is necessary to look for an antonym that can more accurately reflect the opposite meaning. Some antonyms for "putting to sleep" include "reviving," "awakening," "stimulating," "renewing," "energizing," and "rousing." All of these words have connotations of restoring life or vigor to something that was previously inert or asleep.