primum mobile noun phr. [,pri:mǝm 'mǝʊbɪli, ,prʌɪmǝm 'mǝʊbɪli:] Pl. primum mobiles. L15.
[medieval Latin, lit. 'first moving thing', from Latin neut. of PRIMUS adjective + mobilis MOBILE adjective.]
1. In the medieval version of the Ptolemaic system, an outermost sphere supposed to revolve round the earth in twenty-four hours, carrying with it the inner spheres. Cf. MOBILE noun¹ 1, MOVABLE noun 1. L15.

2. transf. = PRIME MOVER 1, 2. E17.

[TahlilGaran] English Dictionary ▲