Speedy, a. [Compar. Speedier; superl. Speediest.]
Etymology: [AS. sp.]
Not dilatory or slow; quick; swift; nimble; hasty; rapid in motion or performance; as, a speedy flight; on speedy foot. I will wish her speedy strength. Shak. Darts, which not the good could shun, The speedy ould outfly. Dryden.
Shades of meaning
Fernald has no entry of its own for speedy; he lists it under nimble.
Where he writes about it:
Alert, which is strictly a synonym for ready, comes sometimes near the meaning of nimble or quick, from the fact that the ready, wide-awake person is likely to be lively, quick, speedy. — from nimble