Page:Dictionary of aviation.djvu/25

 Dictionary of Aviation

��abduction ,aeb'dAk$an n. a leading or drawing away; the act of abducting; the muscular withdrawal, as of a fore* lim or wing, outward or away from the axis or median line of the bedy or part to which the lim is attacht: the epposit of adduction.

abutment-area 3'bAtM9nt,e:-zi-9 n. the area of an abutments: plane.

abutment-fin a'bAtMan^fin n. a fm-like abutmenteplane : distinguisht from directive fin. see under fin.

abutment-plane 3'bAtM3nt,pzxen n. a plane or aerofoil, in an aerodone, which acts as an abutment or support.

acentric a'sentjik adj. net centric; net having the center of resistance coincident with the line of flight : as, an
 * acentr,ic aerodone, aerodrome, or flying#machine.

acrobat 'aekr^baet n. a marsupial quadroped of the genus Acrebates, provided with a patagium by tuhich it is enabled to take flying leaps thru the air; one of the Acrebata.

actinograph ,3ek'tin3,gza:f n. [also spelt actinograf] an in- str,ument for automatically registering the variations of actinic or chemic influence of radiations from any source, especially the sun.

aetinometer ,aekti'n0mi-t3z n. an instrument for mesuring the actinic influence of radiations from the sun, etc.

actinometry ,3ekti'nemi-ti n. the art of mesuring the actinic influence of radiations from the sun, etc.

action-radius 'aekjgn^ee-di-as n. the radius of action of an airship ; the radius of the circle or area of the earth's surface over which the activities, movements, or operations of a dirigible balloon extend; the distance, mesured radi- ally in any direction from the starting-point, tuhich an air- vessel is capable of covering; the cruising-radius.

acuteness a'kgout-nis n. the quality or character of being acute, or long and peinted, as are the wings of some birds ; sharpness, peintedness.

adduction a'dAkfen n. a drawing or bringing toward or in- ward; the act of adducting; the muscular drawing in, as

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