An Etymological Dictionary of Astronomy and Astrophysics

A statement which is based on previous observations and which serves as a starting point for further investigation by which it may be proved or disproved. See also → theory, → model, → ad hoc hypothesis, → Kant-Laplace hypothesis, → arge number hypothesis, → nebular hypothesis, → null hypothesis, → statistical hypothesis, → statistical hypothesis testing.

Etymology (EN): Hypothesis, from M.Fr. hypothèse, from L.L. hypothesis, from Gk. hypothesis “base, basis of an argument, supposition,” literally “a placing under,” from → hypo- “under” + thesis “a placing, proposition,”
from root of tithenai “to place, put, set,” didomi “I give;”
from PIE base *dhe- “to put, to do;” cf.
Mod.Pers. dâdan “to give,”
Mid.Pers. dâdan “to give,” O.Pers./Av. dā- “to give, grant, yield,” dadāiti “he gives;” Skt. dadáti “he gives;” L. dare “to give, offer,” facere “to do, to make;” Rus. delat’ “to do;” O.H.G. tuon, Ger. tun, O.E. don “to do.”

Etymology (PE): Engâré, from engâridan, engâštan “to → suppose.”
Upâdâyan, from upâ-, → hypo-, + dâyan, → thesis.