The expression is "to be on cloud nine." It means to have one's head in the clouds, to be unrealistically euphoric. Perhaps whoever said 'cloud eight' was trying to suggest a less unrealistic euphoria than cloud nine.
You seem to be asking about a distorted version of the idiom "on cloud nine" meaning, extremely happy (cloud nine being a cloud in heaven, or something like that).
"To be" is not an idiom - it's a verb.
The idiom "on cloud nine" (meaning to be in a carefree kind of bliss) appears to have a rather muddled past. The basic idea of having "one's head in the clouds" (meaning rather out of touch with reality for some reason) has been in use in slang since around the 1930s and has evolved over the decades. However, the cloud number has changed along with it in accordance to the different ideas in which the idiom has been used. It is during this time you get related idioms such as "seventh heaven". The use of the specific "cloud nine" seems to have been solidified through music. Both the Temptations in 1969 and George Harrison in 1987 titled albums "Cloud Nine" (in the former's case, the album also contained a song of that title with the lyrics, "I'm feeling fine on Cloud Nine."). The use of "cloud nine" has apparently stuck from that point.
Pest is not an idiom. It's a word.
The idiom "apple shiner" means the teacher's pet.
You seem to be asking about a distorted version of the idiom "on cloud nine" meaning, extremely happy (cloud nine being a cloud in heaven, or something like that).
The idiom "in the cloud of horizon" does not have a standard or widely recognized meaning in the English language. It may be a poetic or metaphorical phrase with a unique interpretation based on the context in which it is used.
"Over the moon" is another way to say that you are very happy. The image evoked is that you are so overjoyed that you have floated off the ground and into space. Another phrase with the same meaning is "on cloud nine." yeh i am on cloud nine!!
"To be" is not an idiom - it's a verb.
The idiom "on cloud nine" (meaning to be in a carefree kind of bliss) appears to have a rather muddled past. The basic idea of having "one's head in the clouds" (meaning rather out of touch with reality for some reason) has been in use in slang since around the 1930s and has evolved over the decades. However, the cloud number has changed along with it in accordance to the different ideas in which the idiom has been used. It is during this time you get related idioms such as "seventh heaven". The use of the specific "cloud nine" seems to have been solidified through music. Both the Temptations in 1969 and George Harrison in 1987 titled albums "Cloud Nine" (in the former's case, the album also contained a song of that title with the lyrics, "I'm feeling fine on Cloud Nine."). The use of "cloud nine" has apparently stuck from that point.
Pest is not an idiom. It's a word.
The idiom "apple shiner" means the teacher's pet.
This is not an idiom. First, it means exactly what it says. Second, when you see AS ___ AS ___ then you are looking at A Simile. Someone is comparing something that is soft to a soft cloud.
The meaning of the idiom in the pink of health means being in good health.
The idiom means impress someone is egg on
It's not an idiom - to cope means to deal with, or to handle
"Old hand" is an idiom meaning having lots of experience.