secularize

verb

(cause to) become more secular, less religious

Wiktionary

verb

Etymology: Etymology tree English secular Proto-Indo-European *-id- Proto-Indo-European *-yéti Proto-Indo-European *-idyéti Proto-Hellenic *-íďďō Ancient Greek -ῐ́ζω (-ĭ́zō)bor. Late Latin -izōder. Middle French -iserbor. Middle English -isen English -ize English secularize From secular + -ize.

To make secular.