An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A small mass of lead or other heavy material, as that suspended by a line and used to measure the depth of water or to ascertain a vertical line (Dictionary.com). → plumb line.

M.E. plumbe, from O.Fr. *plombe, plomee "sounding lead," from L. plumbum "lead (the metal), lead ball," of unknown origin, related to Gk. molybdos "lead."

Gulé "ball, sphere," a variant of golulé, → bullet.

A cord with a weight attached to one end, used to verify a true vertical alignment or to find the depth of water.

→ plumb; → line.

Šâqul, variants šâhul, sâhul, probably from sahi + suffix -ul, variant -âl. The first element sahi "upright, right," variants (Tabari, Torbat-Heydariyeyi: šax) "right, upright, straight, level," colloquial Pers. šaq (o raq = râst) "upright, erect." For the second element → -âl.