What is symbol for more or less?
It depends on what you mean by "more or less".
If more or less is used to indicate approximately or nearly
equal to, then the symbol used is ≈ which look like a wriggly
equals symbol.
If more or less is used for more than or less than but not equal
to, then you would use an equals sign with a diagonal line through
it ≠ which stands for "not equal to"
You are right but if it's more than or less than it would look
like this (less than)<(more)
or (more than)>