Use the “Quick Search” box to locate your required term and/or definition. The following “Search conditions” can be used to refine your search: “Contains”, “Begins with”, “Ends with”, “Equals”, “Does not contain” or “Does not equal.”
Eng ID Term Definition
5161
submarine sound signal
See SOUND SIGNAL.
5162
submarine spring
See SPRING.
5163
submarine transit lane
A LANE where submarines may NAVIGATE under water or at the surface.
5164
submarine valley
See VALLEY.
5165
submarine volcano
A seabed volcano, submerged at the chart sounding datum, which may or may not be active.
5166
submerged
(adj.). Under water; not showing above water. The opposite is UNCOVERED.
5167
submerged rock
A rock covered at the chart sounding datum and considered to be potentially dangerous to navigation.
5168
subordinate station
See STATION.
5169
subpermanent magnetism
See MAGNETISM: PERMANENT.
5170
subplan
An INSET on a SURVEY SHEET used to extend the survey coverage shown on the sheet, or to show small congested areas at enlarged SCALES.
5171
sub-point
That point on the surface of the EARTH at which a particular CELESTIAL BODY is in the ZENITH at a specified TIME. Also called 'geographical ... more
That point on the surface of the EARTH at which a particular CELESTIAL BODY is in the ZENITH at a specified TIME. Also called 'geographical position of a celestial body'. Calledsub-celestial point in Cana­dian terminology. See SUBLUNAR POINT, SUBSOLAR POINT, SUBSTELLAR POINT.
5172
sub-sea completion
See WELL: PRODUCTION.
5173
subsidiary station
See STATION.
5174
subsoil
All naturally occurring matter lying beneath the sea-bed or deep ocean floor.
5175
subsolar point
The GEOGRA­PHICAL POSITION of the SUN; that point on the EARTH at which the SUN is in the ZENITH at a specified TIME.
5176
subsonic
(adj.). Designating or of SPEEDS that are less than that of SOUND.
5177
substellar point
The GEOGRAPHICAL POSITION of a STAR; that point on the surface of the EARTH at which the STAR is in the ZENITH at a specified TIME. Also cal... more
The GEOGRAPHICAL POSITION of a STAR; that point on the surface of the EARTH at which the STAR is in the ZENITH at a specified TIME. Also called subastral point.
5178
substitute centre
A point which, because of its ease of identifica­tion on overlapping PHOTOGRAPHS, is used instead of the PRINCIPAL POINT as a RADIAL CENTRE... more
A point which, because of its ease of identifica­tion on overlapping PHOTOGRAPHS, is used instead of the PRINCIPAL POINT as a RADIAL CENTRE.
5179
substitute map
See MAP.
5180
subsurface current
See CURRENT.