Webster’s Revised Unabridged Dictionary · 1913
Causal
Caus′al (ka̤′zal), a. [L. causalis. See Cause.] Relating to a cause or causes; inplying or containing a cause or causes; expressing a cause; causative.
Causal propositions are where two propositions are joined by causal words. Watts.
Caus′al, n. A causal word or form of speech.
Anglo-Saxon drencan to drench, causal of Anglo-Saxon drincan to drink. Skeat.