A real, positive quantity that measures the magnitude of some number.
For instance, the modulus of a complex number is the square root of
the sum of the squares of its components. Often it means, simply, the
numerical (“absolute”) value of an algebraic quantity.
Etymology (EN): From L. modulus, → module.
Etymology (PE): Peymun, variant of peymâné “a measure either for dry or wet goods; a bushel,
cup, bowl,”
from peymudan, peymâyidan “to measure,”
from Mid.Pers. patmudan, paymudan “to measure (against),”
from *pati-māya-.
The first element *pati- “against, back” (cf. Mod.Pers. pâd-
“agaist, contrary to;” Mid.Pers. pât-; O.Pers. paity “agaist, back,
opposite to, toward, face to face, in front of;” Av. paiti;
Skt. práti “toward, against, again, back, in return,
opposite;” Pali pati-; Gk. proti, pros “face to face with,
toward, in addition to, near;” PIE *proti). The second element
from *mā- “to measure;” O.Pers./Av. mā(y)- “to measure;”
cf. Skt. mati “measures,” matra- “measure;” Gk. metron
“measure;” L. metrum; PIE base *me- “to measure.” Apart from
peymâné, several other terms
in Mod.Pers. are related to this second element, which occurs also as
mun, mân, man, mâ, mu, and mây:
pirâmun “perimeter,” âzmun, âzmây- “test, trial,”
peymân “measuring, agreement,” man
“a measure weighing forty seers”),
nemudan, nemâ- “to show, display,”
âmâdan, âmây- “to prepare.”
