Causal

a.	1.	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.
n.	1.	A causal word or form of speech. Anglo-Saxon drencan to drench, causal of Anglo-Saxon drincan to drink. - Skeat.

Adj.

1.

causal - involving or constituting a cause; causing; "a causal relationship between scarcity and higher prices"

causative