Cleaning marks?

Just Been looking at a website on lenses, where the phrase 'cleaning marks' was used. Cleaning mark?... What's a bleedin' cleaning mark when it's at home? I have heard this expression before, but have never understood what it means. Is it some kind of euphemism for scratch? You know, like on ebay when things are described as 'untested', meaning broken and 'for spares or repair', meaning a piece of worthless junk.
Could someone explain what a cleaning mark is, or better still, show us an example?

I don't have one to show but I'd describe a "cleaning mark" as a scuff as opposed to a scratch (well, that's what I do on eBay listings anyway).

I think of a scratch as something long and thin and deep (deep enough to go through the coating), a cleaning mark more of a faint blur - usually caused by excessive rubbing - sometimes all the way through the coating and sometimes not.

A scratch is more worrying than cleaning marks as it implies damage caused in one go - if the knock was enough to scratch the glass then the lens could have sustained other (internal) damage at the same time. Scuffs appear over a prolonged period of time and don't usually point to any other damage associated with an accident.

Hope that helps.

Ah, yes!. Thanks, Hefty. Sounds sensible.
Makes me wonder what some people are using to clean their lenses, though... Vim?

I buy and sell quite a few used lenses and you'd be horrified at the states some of them get into. I genuinely wouldn't be suprised if some folk out there weren't using scouring pads and Vim!

Think of it a bit like a car washes effect on cars paintwork, after several washes you can see the fine circular scratching.