Also see definition of "Unequal" in Word Study
Unequal
UNEQUAL [isbe]
UNEQUAL - un-e'-kwal: Ezek 18:25,29 for lo' thakhan, "not weighed," "illogical." "Unequally" in 2 Cor 6:14, in the phrase "unequally yoked," heterozugeo, is used of the yoking together of two animals of different kinds (compare the Septuagint of Lev 19:19).
Also see definition of "Unequal" in Word Study