This is a cute name for a girl. Not Jill-y, but Gill-y (like saying fish gills). It is named after the pale pink gilly flower, and it is so fresh sounding, and it is definitely unique. I have never heard it used before. Delicate and beautiful.
Gilly is often a diminutive form of Gillian. Gillie is also a scots term for a servant, especially a boy who aids in a hunting or fishing expidition. The Gillyflower is a type of dianthus (same as carnations).
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