An Etymological Dictionary of Astronomy and Astrophysics

The part of observing time at a telescope which is not directly used for science, such as
the time spent for detector read-out, changing instruments, focusing, etc.

Etymology (EN): → over-; → head; → time.

Etymology (PE): Bâlâ “up, above, high, elevated, height” (variants boland “high, tall, elevated, sublime,” borz “height, magnitude” (it occurs also in the name of the mountain chain Alborz),
Laki dialect berg “hill, mountain;”
Mid.Pers. buland “high;” O.Pers. baršan- “height;” Av. barəz- “high, mount,” barezan- “height;” cf. Skt. bhrant- “high;” L. fortis “strong” (Fr. and E. force); O.E. burg, burh “castle, fortified place,” from P.Gmc. *burgs “fortress;” Ger. Burg “castle,” Goth. baurgs “city,” E. burg, borough, Fr. bourgeois, bourgeoisie, faubourg; PIE base *bhergh- “high”)

• sar, → head.