What does the Russian word bezrazm (безразм) mean?

Probably an abbreviation for something like "bezrazmerniy". "Bez-" means "without" or "minus"; "razmer" means "measure/size/amount." So the whole word would mean something like "dimensionless."

It seems to occur in clothing ads where it appears to mean something like "one size fits all." Like an ad for a belt with lots of holes in it, which you can wear even if your waist is much smaller than the full length of the belt.

So in code, it could refer to a variable-length string or array -- that's just a guess but would that make sense in the context?