Webster's Revised Unabridged Dictionary · 1913

Dialectic

Dialectic , noun

Same as Dialectics.
Plato placed his dialectic above all sciences. — Liddell & Scott

Dialectic , adjective

[Latin dialecticus, Greek {not transcribed}: compare French dialectique. See Dialect.]

1.
Pertaining to dialectics; logical; argumental.
2.
Pertaining to a dialect or to dialects. — Earle

Also: Dialectical