put sth to sleep
to kill an animal that is very ill or very old so that it does not suffer any more

[TahlilGaran] Advanced Learner's Dictionary ▲

put something to sleep
put (something) to sleep
to kill an animal medically.
Mitzie is an old, sick cat, and I think we may have to put her to sleep.

[TahlilGaran] English Idioms Dictionary ▲

put to sleep
put (someone) to sleep
1.
to bore someone very much.
I tried reading one of her novels, but it just put me to sleep.

All those technical discussions put everyone to sleep.

2.
to help someone sleep.
The sound of the crickets puts me to sleep every night.

put (something) to sleep
to kill an animal medically.
Mitzie is an old, sick cat, and I think we may have to put her to sleep.

[TahlilGaran] English Idioms Dictionary ▲

put something to sleep
• put (someone or something) to sleep
to cause someone to sleep/die through drugs or anesthesia
The doctor put the woman to sleep before the operation began.

[TahlilGaran] English Idioms Dictionary ▲

put to sleep
• put (someone or something) to sleep
to cause someone to sleep/die through drugs or anesthesia
The doctor put the woman to sleep before the operation began.

[TahlilGaran] English Idioms Dictionary ▲

put to sleep
v. phr.
1. To cause to fall asleep.
Mother used to put us to sleep by telling us a good-night story and giving us a kiss.
2. To kill with an injection (said of animals).
Dr. Murphy, the veterinarian, put our sick, old dog to sleep.

[TahlilGaran] English Idioms Dictionary ▲

put someone to sleep
put (someone) to sleep
1.
to bore someone very much.
I tried reading one of her novels, but it just put me to sleep.

All those technical discussions put everyone to sleep.

2.
to help someone sleep.
The sound of the crickets puts me to sleep every night.

put (something) to sleep
to kill an animal medically.
Mitzie is an old, sick cat, and I think we may have to put her to sleep.

[TahlilGaran] English Idioms Dictionary ▲

put someone to sleep
• put (someone or something) to sleep
to cause someone to sleep/die through drugs or anesthesia
The doctor put the woman to sleep before the operation began.

[TahlilGaran] English Idioms Dictionary ▲