live wire

[lahyv]

noun

Informal.

1. an energetic, keenly alert person.

live wire

/ laɪv /

noun

1. informal,  an energetic or enterprising person

2. a wire carrying an electric current

Word History and Origins

Origin of live wire¹

An Americanism dating back to 1900–05

Idioms and Phrases

A highly alert or energetic person. For example, Sally's a real live wire; she brightens up any gathering. This metaphoric term transfers a wire carrying electric current to a lively individual. [c. 1900]