put to sleep

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• verb To cause (someone) to sleep.
• verb To help (someone) to bed.
• verb figuratively To render dormant.
• verb euphemistic To kill an animal painlessly, often with an injection; to euthanize.
• verb informal To give a general anesthetic prior to surgery.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• verb help someone go to bed
• verb kill gently, as with an injection