What is a "700-level" question?

Hello experts and fellow-learners,

I don't quite understand the term "700-level" question.
In GMAT, since a score of 700 (or whatever) is derived from individual scores of verbal and quant, how can a verbal question or a math question in isolation be termed a 700-level or a 600-level etc.?

Instead, I feel the difficulty level of a verbal question or a quant question should be better represented by, say, a V40-level or V35-level.... Q51-level or Q49 level etc.

I am not trying to find flaws.... all I wish to understand is what does a 700-level verbal question translate to - V36/V38/V40...?

In practice tests, I hover between verbal scores of 35 and 38, so I wanted to understand whether I can expect to see such questions (700-level) in the actual GMAT.

Thanks in advance for your reply.