There are words which don't quite mean what they originally meant, or what I think they used to mean. It's complicated. What is understood depends a lot on the perception of the listener, general usage varies from place to place, and the relentless churning of fashion will also result in there being subjective differences between people of different ages.
It's all fine; like everything else, language moves along (though I miss a few old friends, and there are many things which I no longer dare say, since the meaning has changed).
A few evenings ago, I agreed with my son that we would go out later on to pick up a takeaway from the fish & chip shop in the village. We went along there about 9pm. The shop was quiet; since our order included a scratch-built pizza, we had to wait about 10 minutes. Two middle-aged couples came into the shop, very pleasant, maybe a little loud (drink had been taken, but nothing unseemly). I would guess they were visitors - North of England accents (I am something of an expert on the North of England), and they got into a slightly complicated exchange with the counter staff, all around the products and terminology you find in chip shops, which vary from area to area. Best not order anything unless you know what it is.
I got briefly involved in offering views on exactly what is the meat constituent of a scary local speciality known as the "King Rib"; which I think is a slab of ultra-processed pork heavily flavoured with something like BBQ sauce. Not recommended, anyway, except after about 4 pints.
Once the preparation of the orders was under way, one of the ladies - very polite, dressed up a little for an evening out, silk scarf, all that - said to me,
"If you don't mind my saying so, you look very..."
...and she paused for a fraction of a second, while she searched for an appropriate word - it seemed quite a long fraction of a second...
"...dapper!" she said, "Yes, that's it: dapper!"
I wasn't at all offended, neither did I take the comment any more seriously than she meant it, though I have to say that I was surprised, for a number of reasons.
(1) People who know me will be aware that my mode of dress is usually warm and comfortable, and, though I hope I do not look completely disreputable, "dapper" is a long way down the list of words I would choose myself. Last time I wore a suit, for example, was at a funeral, and I'm confident the next time I wear one will also be at a funeral, unless I have to appear in court in the interim.
(2) "Dapper" is rather an old-fashioned word, and I associate it with gentle put-downs of older men attempting to dress up. Originally it was used to describe someone who was making a genuine effort to be up-to-date, and I suspect that in the US, for example, it may still have that meaning. I am confident that this lady was not trying to take the piss out of a complete stranger, so this is a usage thing. In a similar vein, if I ever said to a friend that he was looking "with it", he would certainly be quite an elderly friend, and my comment would be (deliberately) an example of British sardonicism, since even I know that nobody says this any more.
(3) "Dapper" has thus, in the UK, become a word used in connection with old men. It is not offensive, but it is one of a number of words which, though generally positive, might be viewed with a little apprehension. If the lady had, for example, stated that I looked "very clean", I might have been nonplussed by the implied parenthesis, "[all things considered]" or similar.
Anyway, I thanked her. Thinking she might have been impressed by my cloth cap, I said something oafish about starting to dress like my father, and we parted with lighthearted laughter. Oh, what fun. The truth is that I had intended to wear my fisherman's beanie hat, which is much warmer, but couldn't find it, so defaulted to the old bunnet. If I had worn my beanie I doubt if I would have been considered dapper. I might have been told I looked like a pile of dirty laundry.
When I first lived here, my next door neighbour, Old George, who was well into his 90s, used to wear a blazer and smart tie on Sundays when he went to the church in Whitekirk, and his trouser-creases were freshly ironed, and his shoes were polished to a frazzle. Now, he was dapper.
Battered King Rib supper - don't ask