nerve

(noun): A bundle of neurons with their connective tissue sheaths, blood vessels and lymphatics.
(noun): A neuron.
(noun): A vein in a leaf; a grain in wood
(noun): Courage, boldness.
(noun): Patience.
(noun): Stamina, endurance, fortitude.
(noun): Audacity, gall.
(noun): (polymer technology) The elastic resistance of raw rubber or other polymers to permanent deformation during processing.
(noun): (in the plural) Agitation caused by fear, stress or other negative emotion.
(noun): Sinew, tendon.
(verb): To give courage.
(verb): To give strength; to supply energy or vigour.

The nerves can be seen through the skin.
Some plants have ornamental value because of their contrasting nerves.
He hasn't the nerve to tell her he likes her. What a wimp!
The web-team found git-sed is really a time and nerve saver when doing mass changes on your repositories
He had the nerve to enter my house uninvited.