An Etymological Dictionary of Astronomy and Astrophysics

To derive as a conclusion from facts or premises.

Etymology (EN): L. deducere “to lead down, derive,” from → de- “down” + ducere “to lead.”

Etymology (PE): Foruhâxtan, foruhâzidan, from foru- “down,” → de- + Mid.Pers. hâxtan, hâzidan “to lead, guide, persuade,” Av. hak-, hacaiti “to attach oneself to, to join,” cf. Skt. sacate “accompanies, follows,” Gk. hepesthai “to follow,” L. sequi “to follow;” PIE *sekw- “to follow.”