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

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

From L. ad "to, with, in," cf. Skt. adhi "near," PIE *ad- "to, near, at."

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."

Addition of adjustments to a theory to save it from being falsified by compensating for anomalies not anticipated by the theory in its unmodified form. Theories that rely on continual, ad hoc adjustments are distrusted.

→ ad hoc; → hypothesis.