E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Gillyflower (g soft)
is not the July-flower, but the French giroflée, from girofle (a clove), called by Chaucer gilofre. The common stock, the wall-flower, the rocket, the clove pink, and several other plants are so called. (Greek karuophullon; Latin, caryophyllum, the clove gillyflower.)