very thin, as thin as a hair
A fishing line made from hair.
The line along one's forehead where hair starts growing.
A very thin line in writing, drawing, or typography.
A very thin fissure.
To make or render precise; to specify.
consistent, clustered close together, agreeing with each other (this does not mean that they cluster near the true, correct, or accurate value)
adhering too much to rules; prim or punctilious
exact, accurate