I suppose another way of phrasing the question might be "Is there anything in your closet that you've had for 15 or more years that still makes you feel fashionable whenever you put it on?"
We fall in love with items and keep them in our closets for many reasons--and we might even pull some of them out and wear them occasionally when the mood hits us, or we are feeling nostalgic. But, if I'm interpreting your question correctly, Una, a "THE ___" type item ought to keep enough of its fashion vibe after a decade, or two or three, to give me the same style punch as it did when it was originally purchased. My physical appearance will have changed, as might some of my style preferences, but the item would still fit my fashion persona well enough to be a contender, if not a workhorse.
Actually, I do have such an item, now that I think about it--and it's not that 80s Burberry coat, obviously. My "THE" item was, and is, my very conventional, English, tan-colored, Gloverall duffle coat. I've worn that coat (well, actually the original and a clone purchased about 25 years later when the original got snitched by my sister) almost every fall since the late 60s. With the exception of a brief period during the Mod 60s, a duffle coat has never really been an "IN" item, nor has it ever really looked odd enough to be out of fashion. I've seen pictures of that coat crop up in every decade, usually worn as I wear it--with tall leather boots, jeans, and a turtleneck. The style of the boots, jeans, and turtleneck might change, but that coat looks pretty much the same, decade to decade, slung over the person's shoulders.
My mid-eighties Coach saddle bag might also be a contender. I just recently resurrected it and its classic look still gives me much pleasure--and even gets me a few compliments from passers-by.
