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Eng ID Term Definition
4401
retardation
In ELECTRONIC NAVIGATION, the amount of delay in TIME or PHASE ANGLE introduced by the resi­stivity of the GROUND over which the SIGNAL is p... more
In ELECTRONIC NAVIGATION, the amount of delay in TIME or PHASE ANGLE introduced by the resi­stivity of the GROUND over which the SIGNAL is pas­sing. In tide terminology, DAILY RETARDATION.
4402
retentivity: magnetic
See MAGNETIC RETENTIVITY.
4403
reticle (or reticule)
A system of wires, hairs, threa­ds, etched lines, or the like, placed normal to the AXIS of a TELESCOPE at its principal FOCUS, by means of ... more
A system of wires, hairs, threa­ds, etched lines, or the like, placed normal to the AXIS of a TELESCOPE at its principal FOCUS, by means of which the TELESCOPE is sighted on a STAR, SIGNAL, or TARGET, or by means of which appropriate readings are made on some SCALE, such as a LEVELLING or STADIA ROD. See also CROSS WIRES, GRATICULE, DIA­PHRAGM. In PHOTOGRAMMETRY, a mark such as a cross or system of lines lying in the image plane of a viewing apparatus and used singly as a refer­ence mark in certain types of monocular instruments or as one of a pair to form a FLOATING MARK as in certain types of STEREOSCOPES.
4404
reticle ring
The ring across which the system of wires, hairs, threads, or the like of a RETICLE are stretched; or the ring which supports the glass DIAP... more
The ring across which the system of wires, hairs, threads, or the like of a RETICLE are stretched; or the ring which supports the glass DIAPHRAGM when the RETICLE is a system of lines etched on glass.
4405
retired line of position
A LINE OF POSITION which has been moved backward along the COURSE line to correspond with a TIME previous to that at which the line was esta... more
A LINE OF POSITION which has been moved backward along the COURSE line to correspond with a TIME previous to that at which the line was established. Called a transferred position line in British terminology.
4406
retrogression of a beach
See RECESSION OF A SHORELI­NE.
4407
reverberation
Continuation of RADIANT ENERGY, par­ticularly SOUND by multiple REFLECTION. SOUND scattered towards the source, principally from the ocean s... more
Continuation of RADIANT ENERGY, par­ticularly SOUND by multiple REFLECTION. SOUND scattered towards the source, principally from the ocean surface (surface reverberation) or BOTTOM (bottom reverberation), and from small scattering sources in the medium such as bubbles of air and sus­pended solid matter (volume reverbera­tion).
4408
reverse azimuth
See AZIMUTH: BACK.
4409
reversing current
See CURRENT.
4410
reversing thermometer
See THERMOMETER.
4411
reversing water bottle
See WATER BOTTLE.
4412
revetment
Facing of stone or other material, either permanent or temporary, placed along the edge of a stream to stabilize the bank and to protect it ... more
Facing of stone or other material, either permanent or temporary, placed along the edge of a stream to stabilize the bank and to protect it from the erosive action of the stream.
4413
revolution
Motion of a CELESTIAL BODY in its ORBIT; circular motion about an AXIS usually external to the body. The terms revolution and ROTATION are o... more
Motion of a CELESTIAL BODY in its ORBIT; circular motion about an AXIS usually external to the body. The terms revolution and ROTATION are often used interchangeably but, with reference to the motions of a CELESTIAL BODY, revolution refers to the motion in an ORBIT or about an AXIS external to the body, while ROTATION refers to motion about an AXIS within the body. Thus, the EARTH revolves about the SUN annually and rotates about its AXIS daily.
4414
revolver
See FIX: CIR­CULAR.
4415
revolving light
See LIGHT: ROTATING.
4416
rho-teta system
Positioning system measuring the di­stance (rho) and direction (teta) from an existing control station to a mobile or another point.
4417
rhumb
See RHUMB LINE.
4418
rhumb line
A line on the surface of the EARTH making the same oblique angle with all MERIDIANS; a LOXODROME spiralling toward the POLES in a constant t... more
A line on the surface of the EARTH making the same oblique angle with all MERIDIANS; a LOXODROME spiralling toward the POLES in a constant true direc­tion. PARALLELS and MERIDIANS, which also maintain constant true directions, may be considered special cases of the rhumb line. A rhumb line is a straight line on a MERCATOR PROJECTION. Sometimes shortened to rhumb.
4419
rhumb line sailing
See SAILING.
4420
ria
A long narrow INLET, with DEPTH gradually dimin­ishing inward; a CREEK. Any broad RIVER opening into the OCEAN.