The angle between each side of the thread.
Related Terms 
ABSORBER
That part of the low side of an absorption system, used for absorbing vapor refrigerant.

WEATHER SIDE
The side of a ship exposed to the wind.

HARMONIC FUNCTION
Any real function that satisfies a certain equation. In its simplest form, as used in tide and tidal current predictions, it is a quantity that varies as the cosine of an angle that increases uniformly with time

GREENWICH HOUR ANGLE
Angular distance west of the Greenwich celestial meridian; the arc of the celestial equator, or the angle at the celestial pole, between the upper branch of the Greenwich celestial meridian and the hour circle of a point on the celestial sphere, measured westward from the Greenwich celestial meridian throug

GRID RHUMB LINE
A line making the same oblique angle with all grid meridians. Grid parallels and meridians may be considered special cases of the grid rhumb line.

GRID MAGNETIC ANGLE
Angular difference in direction between grid north and magnetic north. It is measured east or west from grid north. Grid magnetic angle is sometimes called GRID VARIATION or GRIVATION.

HORIZONTAL DANGER ANGLE
The maximum or minimum angle between two points on a chart, as observed from a vessel, indicating the limit of safe approach to an offlying danger.

SHELL PLATING
The plates forming the outer side and bottom skin of the hull

PRESSURE DROP
Resistance to flow created by the element (media) in a filter or other equipment. Defined as the difference in pressure upstream (inlet side of the unit) and downstream (outlet side of the unit).

PARTICLE EROSION
Occurs when fluidentrained particles moving at high velocity pass through orifices or impinge on metering surfaces or sharp angle turns.
