An example of conjugal used as an adjective is the phrase "conjugal relations" which means a physical, sexual relationship between a married couple.
Origin of conjugalClassical Latin conjugalis from conjunx, conjux, husband or wife from com-, together + base akin to Classical Latin jugum, yoke, jungere, join
Origin of conjugalLatin coniugālis from coniūnx coniug- spouse from coniungere to join in marriage ; see conjoin .
From Middle French
conjugal - Legal Definition