Gussuri (Having a Good Night's Sleep)

There is the Japanese adverb "gussuri" (ぐっすり), which implies being deep asleep.

Actually, a Japanese TV show introduced that "gussuri" comes from "good sleep" in English, so I think that many Japanese people believe the etymology.

However, this term has been used since the Edo period, which was the period when Japan had closed the country to foreign commerce, hence it's hard to think that it came from English.

Originally, gussuri was used as an onomatopoeia that means "jūbun-ni" (十分に - fully) or "sukkari" (すっかり - totally).

It is thought that since it was often used with the verb "nemuru" (眠る - sleep), it came to have the meaning as having a good night's sleep.

ぐっすり

深く眠るさまを表す副詞として、「ぐっすり」があります。

実は、あるテレビ番組でぐっすりは英語の "good sleep" から来ていると紹介されたため、それを信じている日本人は少なくありません。

しかし、この言葉は江戸時代、すなわち日本が鎖国していた時代から使われていたため、英語から来ているとは考えにくいです。

ぐっすりは元々「十分に」「すっかり」という意味で使われていた擬態語で、「ぐっすり眠る（十分に眠る）」「ぐっすり寝てしまった（すっかり寝てしまった）」などの用例から、現在では主に「深い眠り」を意味するようになったとされています。

• There is the Japanese adverb "gussuri," which implies being deep asleep.
• There is the Japanese adverb "gussuri," which implies sleeping soundly.

• However, this term has been used since the Edo period, which was the period when Japan had closed the country to foreign commerce, hence it's hard to think that it came from English.
• However, this term has been used since the Edo period, which was the period when Japan had closed the country excluded itself from foreign commerce; hence it is an arguable statement that "gussuri" originates from English.

  For the last sentence, you can also say "therefore I do not agree that 'gussuri' comes from English".

• It is thought that since it was often used with the verb "nemuru" (眠る - sleep), it came to have the meaning as having a good night's sleep.
• It is thought that since it was often used with the verb "nemuru" (眠る - sleep), its meaning extended to "having a good night's sleep.

  extend here means: to stretch, draw, or arrange in a given direction, or so as to reach a particular point.

• Gussuri (Having a Good Night's Sleep)
• Gussuri (Having a Good Night's Sleep)

  kanji?

• There is the Japanese adverb "gussuri," which implies being deep asleep.
• There is the Japanese adverb "gussuri," which implies being in a deep asleep.

  implies being deep asleep --> implies being in a deep sleep -
  
  implies sleeping soundly - as lee suggested
  implies being in deep sleep
  implies deep sleep
  implies being deeply asleep

• Actually, a Japanese TV show introduced that "gussuri" comes from "good sleep" in English, so I think that many Japanese people believe the etymology.
• Actually, a Japanese TV show introduced (suggested?)that "gussuri" came from "good sleep" in English, so I think that many Japanese people believe the (that) etymology.

  comes --> came - You're referring to a past event.

• However, this term has been used since the Edo period, which was the period when Japan had closed the country to foreign commerce, hence it's hard to think that it came from English.
• However, this term has been used since the Edo period, which was the period when Japan had closed the country to foreign commerce, hence it's hard to think that it came from English.

  Your's is fine.
  
  However, this term has been used since the Edo period, the period when Japan had closed the country to foreign commerce, hence it's hard to think that it came from English.
  
  However, this term has been used since the Edo period, the period when Japan was closed to foreign commerce, hence it's hard to think that it came from English.
  
  
  However, this term has been used since the Edo period, when Japan was closed to foreign commerce, hence it's hard to think that it came from English
  
  What can I say, my philosophy is that the fewer words I use the fewer chances I have to screw up. ;o)

• Originally, gussuri was used as an onomatopoeia that means "jūbun-ni" (十分に - fully) or "sukkari" (すっかり - totally).
• Originally, gussuri was used as an onomatopoeia that means "jūbun-ni" (十分に - fully) or "sukkari" (すっかり - totally).

  The sentence is ok.
  
  What parts of gussuri, or is gussuri, itself an example of onomatopoeia? Onomatopoeia means that a word(s) is/are mimicking the sound of something else, right? Wo, what are they mimicking?
  
  You sound do a post on onomatopoeia from a Japanese perspective. Everytime I think I'm starting to understand it I find out I don't.

• It is thought that since it was often used with the verb "nemuru" (眠る - sleep), it came to have the meaning as having a good night's sleep.
• It is thought that since it was often used with the verb "nemuru" (眠る - sleep), it came to have the meaning of having a good night's sleep.

  as --> of

We have the expression:

sound asleep, fast asleep - in a deep sleep


sleep like a log - immobile like a log
sawing logs - an extension of the previous - snoring loudly

ぐっすり
早い眠り