Variant of Lindsay, from Old English meaning 'Lincoln's island or wetland.'
Lindsy is a warmly unconventional spelling of Lindsay — or Lindsey — a name with roots reaching back to the Anglo-Saxon and Scottish landscape. The name derives from the Old English place name Lindsey, a region in Lincolnshire whose first element likely comes from "Lind," the ancient name of the town Lincoln (itself from the Latin Lindum Colonia), possibly connected to the linden tree or to a pool. The suffix "-ey" means island or water-meadow, giving the name a quietly pastoral geography: a place by the water, sheltered by lime trees.
As a surname, Lindsay was carried by one of Scotland's great noble families; the Earls of Crawford bore it for centuries and it appears across Scottish records from the twelfth century onward. The poet Sir David Lindsay of the Mount (c. 1486–1555) was one of the most influential Scottish literary figures of the Renaissance, and the family name passed steadily into given-name use over the following centuries.
By the twentieth century Lindsay and its variants had become popular on both sides of the Atlantic, given equally to boys and girls before settling more firmly into feminine territory by the 1970s. The spelling Lindsy strips the name back slightly — losing the conventional "-ey" or "-say" endings — and gives it a quieter, more personal feel, the kind of spelling a family might have arrived at through phonetic intuition or individual variation. It keeps the name's pleasant sound while marking it as distinctively its bearer's own.