Well I know the "atheos" word from Wikipedia: http://en.wikipedia.org/wiki/Atheist#Etymology
Note the use of the separation of ἀ and θεός (god), being the combination of the two words "without"(http://en.wikipedia.org/wiki/Privative_a) and "god".
Quote:In early Ancient Greek, the adjective atheos (ἄθεος, from the privative ἀ- + θεός "god") meant "godless".
Note the use of the separation of ἀ and θεός (god), being the combination of the two words "without"(http://en.wikipedia.org/wiki/Privative_a) and "god".