An Etymological Dictionary of Astronomy and Astrophysics

For the specific purpose at hand, as opposed to a general solution; also, by extension, improvised or impromptu.

Etymology (EN): From L. ad “to, with, in,” cf. Skt. adhi “near,” PIE *ad- “to, near, at.”

Etymology (PE): Pad im, from Mid.Pers. pad “to, at, for, in” (Mod.Pers. bé “to, for, in, on, with, by”);
O.Pers. paity “agaist, back, opposite to, toward, face to face, in front of;” Av. paiti “to, toward, in, at;” cf.
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)

• Mid.Pers. im “this;” from Old.Pers./Av. ima “this;” Skt. imá; cf. Lori (Laki) im “this side.” The Mid.Pers. im occurs in Mod.Pers. as em- in emruz “today,” emšab “tonight,” and emsâl “this year.”