I saw the word 'pre-loved' in a story in yesterday's Metro, a free newspaper handed out at stations, about Transport for London donating unclaimed lost property to charity (I can't find the article online, but this one is the same story). Toys would be donated to the Salvation Army, who would distribute them to disadvantaged families for Christmas. The toys were described as 'pre-loved', a euphemism for second-hand.
I won't go into great detail about the history of the word 'pre-loved', as Stan Carey over at Sentence First has already written a much better account than I could write. Pre-loved is in the OED, though; it went in in March 2007, and the first citation is from a Lima (Ohio) News article of 1972.
What prompted me to write this post was remembering that I have seen the phrase 'gently worn' a fair bit recently, another euphemism for 'second-hand', this time referring to clothes. Less common, but still with over 7 million hits online, is the similar 'gently used'.
In many contexts the word 'second-hand' or 'used' has no negative connotations. Most people are quite happy to buy a used car, and shopping streets are full of charity shops selling second-hand goods. These are very popular in the UK. However, I can understand that in the context of giving presents to children you might not want to emphasise that the toys are second-hand. Being something of a cynic, I think that dress agencies (another euphemism for second-hand clothing shops), eBay sellers and the like feel that using the phrase 'gently worn' makes the item sound nearly new (another common euphemism) and thus justifies a higher price. In all my years helping out behind the counter at Scouts' jumble sales I don't remember any of us ever referring to anything on sale as anything other than 'old' or 'second-hand', and that was probably because we were charging 10 pence or so an item -- rather than it having to do with the relative wear and tear or quality of the goods.
It is often said that English has no true synonyms. Even if two words have the same meaning they often have different connotations or evoke different images (moist and damp, for instance). Certainly this is true about all the words that mean broadly 'old'. Clothing described as 'vintage' (or gently worn), or furniture described as antique, will probably have a high price tag; it would be a foolish seller who described an item as 'old' or 'old-fashioned'.