Nerve

n. any bundle of fibers belonging to the nervous system that transmits sensations and messages between the brain and other parts of the body; tendon (Anatomy); vein in a leaf or insect wing; courage; daring; rude boldness (Informal)

v. embolden; gather courage, strengthen oneself; cheer, encourage, inspire

A nerve is an enclosed, cable-like bundle of axons (the long, slender projection of a neuron). Neurons are sometimes called nerve cells, though this term is technically imprecise since many neurons do not form nerves, and nerves also include the glial cells that ensheath the axons in myelin.
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Nerve a cordlike structure comprising a collection of nerve fibers that convey impulses between a part of the central nervous system and some other [more]Nerve - Community and Resources

Noun
1. any bundle of nerve fibers running to various organs and tissues of the body
(synonym) nervus
(hypernym) fiber bundle, fibre bundle, fascicle, fasciculus
(hyponym) motor nerve
(part-meronym) radicle
2. the courage to carry on; "he kept fighting on pure spunk"; "you haven't got the heart for baseball"
(synonym) heart, mettle, spunk
(hypernym) courage, courageousness, bravery
(derivation) steel
3. impudent aggressiveness; "I couldn't believe her boldness"; "he had the effrontery to question my honesty"
(synonym) boldness, brass, face, cheek
(hypernym) aggressiveness
(hyponym) audacity, audaciousness
Verb
1. get ready for something difficult or unpleasant
(synonym) steel
(hypernym) brace, poise
(derivation) heart, mettle, spunk

v. irritate, harass, tease, prick