sigmoid sinus: an S-shaped dural sinus on the temporal and occipital bones
venous sinus: a wide channel containing blood; does not have the coating of an ordinary blood vessel
volt: a unit of potential equal to the potential difference between two points on a conductor carrying a current of 1 ampere when the power dissipated between the two points is 1 watt; equivalent to the potential difference across a resistance of 1 ohm when 1 ampere of current flows through it