Let me get this straight. This U.S. company is called Proper Suit, it sells bespoke suits, but its website doesn’t mention the word “bespoke.” (Thanks, Nancy Friedman.)
The Saville Row Bespoke Association, a watchdog group, insists that ‘bespoke’ means made-to-order, tailor-made, or personalized.
The opposite is ‘off-the-rack.’ Between the extremes is a grey area.
(I write ‘grey’ because ‘grey’ seems to me to be more grey than ‘gray.’)
It is slightly more complicated than that. The Saville Row Bespoke Association actually polices the use of the term ‘Savile Row Bespoke’ in the context of suits. There is no suggestion that you cannot buy bespoke from other places. Rather, bespoke refers to the standard of fitting and detail – typically specifically-ordered (“bespoken for”) fabric, handsewing, full canvassing and multiple fittings. You can buy excellent bespoke clothing in Naples, or beyond the Row in London. Off-the-rack (OTR) or ready-to-wear (RTW) are the things you buy in shops, cut to standard blocks. The grey zone is indeed made-to-measure (MTM) in which blocks are altered to get closer to your shape.
American here. I had never heard this word until maybe two years ago, and I get the impression there is a particular resistance to this word for being too pretentious. In this case, it’s not filling any lexical gap in American vocabulary (we say “custom suit”) so to change it or adopt it seems like someone is trying too hard. A reader’s comment on a New York Times article about bespoke suits: “This word is taking over NY and really doesn’t need to be.” (www.nytimes.com/2012/09/09/magazine/whats-a-4000-suit-worth.html?pagewanted=all&_r=0)
Let me get this straight. This U.S. company is called Proper Suit, it sells bespoke suits, but its website doesn’t mention the word “bespoke.” (Thanks, Nancy Friedman.)
notoneoffbritishisms.com 
The Saville Row Bespoke Association, a watchdog group, insists that ‘bespoke’ means made-to-order, tailor-made, or personalized.
The opposite is ‘off-the-rack.’ Between the extremes is a grey area.
(I write ‘grey’ because ‘grey’ seems to me to be more grey than ‘gray.’)
The grey area is ‘made to measure’ isn’t it?
It is slightly more complicated than that. The Saville Row Bespoke Association actually polices the use of the term ‘Savile Row Bespoke’ in the context of suits. There is no suggestion that you cannot buy bespoke from other places. Rather, bespoke refers to the standard of fitting and detail – typically specifically-ordered (“bespoken for”) fabric, handsewing, full canvassing and multiple fittings. You can buy excellent bespoke clothing in Naples, or beyond the Row in London. Off-the-rack (OTR) or ready-to-wear (RTW) are the things you buy in shops, cut to standard blocks. The grey zone is indeed made-to-measure (MTM) in which blocks are altered to get closer to your shape.
American here. I had never heard this word until maybe two years ago, and I get the impression there is a particular resistance to this word for being too pretentious. In this case, it’s not filling any lexical gap in American vocabulary (we say “custom suit”) so to change it or adopt it seems like someone is trying too hard. A reader’s comment on a New York Times article about bespoke suits: “This word is taking over NY and really doesn’t need to be.” (www.nytimes.com/2012/09/09/magazine/whats-a-4000-suit-worth.html?pagewanted=all&_r=0)