A smell-a-like is a perfume that smells like a designer fragrance but with a different name and packaging, and at a cheaper price. A smell-a-like isn't an exact copy, but often smells very similar.
BLOGGER REVIEWBonkers about Perfume (12 Nov 2009)
I bought a bottle on the spot - £3.99 is a bargain by any standards. It smelt to me like a perfume that cost up to five times that ie what I would consider as the lower end of the designer market... Okay, so the Lidl one is not an exact replica, but eight of the eleven notes listed for it also feature in Luminous. Even to my neophyte nose, that counts as a "ghostly resemblance".