connubial kuh-NOO-bee-ul; -NYOO-, adjective:
Of or pertaining to marriage, or the marriage state; conjugal; nuptial.

Connubial comes from Latin conubialis, from conubium,”marriage, intermarriage,” from con-, “with, together” + nubere, “to veil, to marry.” It is related to nubile, “of an age suitable for marriage; hence, sexually mature and attractive.”