Un-tēach', v. t.

verbtransitive

v. t. [imp. & p. p. UNTAUGHT; p. pr. & vb. n. UNTEACHING.] To cause to forget, or lose from memory, as what has been taught.

Experience will unteach us. Browne.

One heart laid open were a school Which would unteach mankind the lust to shine or rule. Byron.