I. (ˌ)ēˌlȯŋˈgāshən, ə̇ˌ- also -läŋ- noun
( -s )
Etymology: Middle English elongacioun, from Medieval Latin elongation-, elongatio, from Late Latin elongatus (past participle of elongare to withdraw) + Latin -ion-, -io -ion
1.
a. : the angular distance of a celestial body from another around which it revolves or from a particular point in the sky
the elongation of a planet from the sun
the elongation of an eclipsing variable
— see greatest elongation
b. : the daily extreme east or west position of a star with reference to the north celestial pole
the elongations of the North Star
2. obsolete : removal to a distance : remoteness
II. noun
( -s )
Etymology: elongate (I) + -ion
1.
a. : a lengthening or state of being lengthened : protraction , extension
the elongation of a muscle under tension
elongation of the apex of a plant
b. : the total deformation in the direction of load or per unit of length caused by a tensile force ; sometimes : the maximum permanent stretch per unit of original length induced in a body by a force that causes it to break
2. : something that is elongated : prolongation , continuation
the arm may be considered a specialized elongation of the earlier fin