' Academic Press
`Dictionary
`
`of Science and _
`
`

`

`~-.ears in the ma
`onary of Scienc
`..-ark covering
`.. g complete, u
`, 0 · science and
`~:inguished by
`_-1- disciplines
`:oo ized leaden
`--iew of the an
`.-...- and implic
`s~~ded for eas;
`r1:s off er practi1
`h e tennino
`: rstand.
`
`of these " Vii
`~' e contribut
`_\.suophysics
`Biochemistr)
`Biology by R
`chemistry b
`Crystallogra
`Electromag11
`Eridocrinolo
`Entomolog)
`Evolution b -
`Geography
`, Microbiolu
`, Oceanogra1
`• Plasmids b
`• Surgery by
`• Vaccinolo:
`
`cover photo~
`J.M. Ottino,.
`'" orthwester
`
`Coexistenc1
`viscou s flm
`plates fixec
`rotating tu
`and folds r
`mixes at a
`graphic th
`chosen to
`classify QI
`vocabula1
`
`Jacket des
`
`This book is printed on acid-free paper. @)
`
`Copyright © 1992 by ACADEMIC PRESS, ll'IC.
`All Rights Reserved .
`No part of this publication may be reproduced or transmitted in any fom1 or by any
`means, electronic or mechanical, including photocopy, recording, or any information
`storage and retrieval system, without permission in writing from the publisher.
`
`Academic Press, Inc.
`1250 Sixth Avenue, San Diego, California 92101-43 11
`
`United Kingdom Edition published by
`Academic Press Limited
`24--28 Oval Road, London NW! 7DX
`
`Library of Congress Cataloging-in-Publication Data
`
`Academic Press d ictionary of science and technology I edited by
`Christopher Morris
`p.
`cm.
`ISBN 0-12-200400-0
`1. Science--Dictionaries. 2. Technology--Dictionaries.
`I. Morris, Christopher G.
`II. Academic Press.
`Ill. Title:
`Dictionary of science and technology.
`Ql23.A33 1991
`503--dc20
`
`PRJNTED IN THE UNITED STA TES OF AMERICA
`92 93 94 95 96 97
`DO
`9 8 7 6 5 4 3 2
`
`I
`
`90-29032
`CIP
`
`

`

`substrate mycelium
`
`2126
`
`successive approxi ...........
`
`substrate mycelium Mycology. hyphal masses or mycelium that grow
`on the surface to which they are attached. Also. VEGETATIVE ~1YCELiuM.
`substratosphere Meteorology. the atmospheric region that is of indef(cid:173)
`inite extent beneath the stratosphere.
`substratum Geology. any solid layer occurring beneath the true soil or
`superficial deposits. Agriculture. another tem1 for the subsoil. Biology .
`the base on which a nonmotile organism lives.
`substring Computer Programming. a contiguous portion of a string.
`substructure Cii·i1 Engineering . 1. the part of any struct ure that is
`below ground. 2. specifically. the foundation or piers of a bridge.
`subsumed clause Artificial !melligence. in predicate calculus. a
`clause that can be deleted because another stronger clause is present;
`e.g., P(x) subsumes P (.r) v Q(x) because whenever P(x) is true, then
`P(x) v Q(x ) must also be true.
`subsurface contour see STRUCTURE CONTO UR.
`subsurface current Oceanography. an ocean current flowing beneath
`the surface, usually below the main thermocline and often in a different
`direction from that of the surface currents.
`subsurface flow see INTERFLOW.
`subsurface geology Geologv. a branch of geology concerned with the
`study and correlation of geologic features and processes occurring be(cid:173)
`neath the earth 's surface. Also, UNDERGROUND GEOLOG Y.
`subsurface hydrology Hydrology. the branch of hydrology dealing
`with the study of underground water. as opposed to surface water.
`subsurface ice see GROUND 1cE.
`subsurface tillage Agriculture. a form of plowing in which under(cid:173)
`ground blades stir the soil , but leave surface vegetation in place. Also.
`subsurface till.
`subsurface waste disposal Engineering . a method of disposing of
`wastes by pumping them into porous rock and certain other formations.
`subsurface wave Electromagne tism. an electromagnetic wave that
`propagates through land or water rather than on the earth's surface; at(cid:173)
`tenuation is significant for such waves above about 35 kilohertz.
`subsynchronous Electricity. having a frequency that is a submul tiple
`of the driving frequency.
`subsystem Science. a portion of a system that can be treated as a single
`element in the main system, but that can also be considered a distinct
`system itself.
`subtend Botany . of a plant or plant part, to grow beneath and close to
`another plant or part, often embracing or enclosing it. Mathematics. to
`extend under. stretch across, or be opposite to, as a chord and an arc.
`subtense bar Engineering. in surveying, a horizontal bar used for dis(cid:173)
`tance measurement by determining the arc it subtends as viewed from
`the meas uring point.
`subtense technique Civil E11g111eeri11g. a technique used in surveying
`to measure distances, in which a transit angle subtended by the subtense
`bar permits the calculation of the distance between the transit and bar.
`subterranean [sub 't;i ra 'ne <in] Geology. relating to or located in the re(cid:173)
`gion beneath the surface of the earth, especially the land surface; under(cid:173)
`ground.
`subterranean lee see GROUND 1cE.
`subterranean stream Hydrology. a stream flo wing beneath the sur(cid:173)
`face through a cave or group of connected caves.
`subterranean water see GROUNDWATER .
`subtilin Microbiology . an antibiotic that is produced by the soil bac(cid:173)
`terium Bacillus subtilis; effective against organisms such as Gram-posi(cid:173)
`tive bacteria and the tubercle bacillus.
`subtilisin Biochemistry. an extracellular protease produced by bacteria
`of the genus Bacillus (such as B . amyloliquefaciens or B . subtilis ) that
`digest protein molecules; used as an active agent in detergents and in
`protein-structure research. Also, NAGAROSE.
`subtract Mathema tics. to carry on a process of subtraction; remove one
`number or quantity from dnother.
`subtracter Compwer Te chnology. a circuit that performs arithmetic
`subtraction operations on binary numbers.
`subtraction Math ematics. the process by which, for two given numbers
`or quantities, one is removed from the other to give a third; the opera(cid:173)
`tion that is inverse to addi tion. It is a noncomm utative binary operation
`denoted by the minus sign;;_"; a - b =a + (- b), where - b is the additive
`inverse of b. <;+" usually refers to the operation of an Abelian group or
`the group operation in a ring. module, or vector space over which the
`other operations distribute.
`subtractive primaries Optics. the colors that are complementary 10
`red, blue, and green in subtractive printing processes; respectively ,
`cyan, yellow, and magenta.
`
`·-..,,. • .....,,,,,.,,,,_,
`
`subtractive process Optics. the process that re pr ~ ---
`means of transparent inks or dyes in their complemen a; .
`used in photography and printing.
`subtractor Electronics. an operational amplifier circ u::
`determined by the difference between the input signal>.
`subtrahend Mathematics. a quanti ty that is to be su;_;::
`other quantity (the minuend).
`subtribe Svstemarics. a taxonomic rank immediate!\· 1x·
`subtropical Mereorology. 1. of or relating to the s~
`ing on the tropics; nearly tropical.
`subtropical anticyclone see SUBTROPICAL HIGH.
`Subtropical Convergence Oceanography. the
`tween warm subtropical and cold subpolar waters "',
`currents tend to converge; the term generally refers _
`southern convergence zone around 40°$, but it may al
`defined northern zone between 20°N and 28°N.
`subtropical cyclone Meteorology. a low-level atrr. • .,.
`representation of a cutoff low on a surface chart.
`subtropical easterlies see T ROPICAL EASTERLIES.
`subtropical easterlies index Meteorolog y. a sea: ~
`the strength of easterly winds in the northern subtrop:::(cid:173)
`the average sea-level pressure difference between J ·.
`expressed in meters per second as the east-west co :-.
`sponding geostrophic wind.
`subtropical high Meteorology. any of the semipe:-:7'
`sure systems that lie over the oceans of the subtroi; :
`belt and are best developed during the summer sea
`CAL ANTICYCLONE, OCEAN IC ANTICYCLO NE, OCEA!\ IC H: -
`subtropical high-pressure belt Meteorology. e::'.'k(cid:173)
`high atmospheric pressure that are formed by subtrop._
`tered. in the mean, near 30° latitude N and S. Also. su
`subtropical westerlies see WESTERLIES .
`subtropics Meteorology. ei ther of two latitudin :
`tropics and the temperate regions, roughly bet we.on : :
`tude but varying in width according to continental ir.:(cid:173)
`subulate Botany. of or related to a leaf that is slen~- -
`tapering from base to a fine-pointed apex .
`Subulitacea Paleontology. a large superfami ly of PL::
`belonging to the subclass Prosobranchia of the oroc :!.•"-·'-"·~,.~~-~·.­
`generally characterized by a spindle or awl shape. u~
`ters high ; extant from the Ordovician to the Permia::
`Subuluridea see H ETERAKIDAE.
`subumbrella ln verrebrate Zoology . the cone.a,·.: u::-~
`lenterate medusa.
`suburb Cii·i1 Engineering. a smaller comm uni :- . ¥
`dential, that lies adjacent to or al the edge of a maj<X .
`subvariety Systematics. a botanical taxonomic rarj;
`species or subspecies.
`subversion Military Science. action designed to
`economic, psychological, or political strength of a -
`undermining the morale, loyalty. or reliability of it';
`subvert Military Science. to carry on an operation c-:
`subviral agent Microbiology. any viroid or oihe:
`entity that lacks at least one essential feature of a vi.--
`subviral particle Virology. an intermediate form c'.
`ing in certain components, that is formed during rt:.o- -•
`subvolution Surgery. the turning up of a flap of r.:
`that the cutaneous surface comes in contact with t:.:: -
`section to prevent adhesions, especially for a ptef' i ·-
`subwaking Neurology . a state of awareness
`, : •
`plete consciousness.
`subway Civil Engineering. 1. an undergro und rail J
`train that is part of such a system. 3. especially iic 3 -
`gound passage, as beneath an urban street.
`subway-type transformer Electricity. a tr2:: ~-.
`structed so that it can be installed in an undergrou:-=
`Sucaryl Organic Chemistry. a trade name for sodi· -
`fici al sweetener formerly in wide use.
`succession Ecology . I. the progressive replace.:::
`of one type of community by another. 2. the prl":.e<
`takes place in a community, which can be i nd :..:~­
`factors or by the species ' own intrinsic character.: :::_
`succession cropping Agro110111y. the grow in~ "
`one after the other on the same land in one growirr;
`successive approximation Behavior. see SH . .,PZ
`
`•
`
`