E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Ophelia gives the queen a daisy to signify that her light and fickle love ought not to expect constancy in her husband. So the daisy is explained by Greene to mean a Quip for an upstart courtier. (Anglo-Saxon dges ege, days eye.)
The word is Days eye, and the flower is so called because it closes its pinky lashes and goes to sleep when the sun sets, but in the morning it expands its petals to the light. (See VIOLET.)