Vivacious is a related term of nippy.
As an adjective vivacious
is lively and animated; full of life and energy.
As a noun nippy is
(uk|dated) a waitress in a.
Lively and animated; full of life and energy.
(rare) Difficult to kill.
* (lively and animated) animated, bubbly, ebullient, high-spirited, lively, vibrant, exciting
(informal) Of the weather, rather cold.
(informal) fast; speedy
* Melanie Allen, Customer Relations Management (page 6)
- Gosh, it's a bit nippy today: I'd better wear my gloves.
- A Rolls Royce will not do if you need an economical, nippy car that is easy to park.