explosive sleep

[Itasan]

'Dead sleep' and 'sleep like a log' are
colloquial expressions, right?
Are there any other colloquial or slang
expressions?
In Japan, young people say BAKUSUI,
literally 'explosive sleep'. That's very
funny (strange), isn't it?
Thank you.

[Marylin]

Originally Posted by Itasan

'Dead sleep' and 'sleep like a log' are
colloquial expressions, right?
Are there any other colloquial or slang
expressions?
In Japan, young people say BAKUSUI,
literally 'explosive sleep'. That's very
funny (strange), isn't it?
Thank you.

The ones I am familiar with are: dead asleep, fast/sound asleep, to be out like a light, to be out cold.

[Itasan]

Thank you very much.
Why 'like a LIGHT', why 'be out COLD' if I may ask?
Itasan

[Marylin]

Originally Posted by Itasan

Thank you very much.
Why 'like a LIGHT', why 'be out COLD' if I may ask?
Itasan

You're welcome.

Here's the explanation from an online dictionary:

Also, out for the count; out like a light. Unconscious; also, asleep. For example, He crashed into the wall and was out cold, or Willie punched him too hard, and he was out for the count or Don't call Jane; she's out like a light by ten every night. The adjective cold refers to the lack of heat in a dead body and has been used to mean “unconscious” since the second half of the 1800s. The first variant comes from boxing, where a fighter who is knocked down must get up before the referee counts to ten or be declared defeated; it dates from about 1930. The last variant alludes to turning out a light and dates from the first half of the 1900s.
lol:

[Itasan]

Thank you very much, Marylin.
Itasan