Source : Webster's Revised Unabridged Dictionary (1913)

Clearstarch \Clear"starch`\, v. t. [imp. & p. p.
   {Clearstarched}; p. pr. & vb. n. {Clearstraching}.]
   To stiffen with starch, and then make clear by clapping with
   the hands; as, to clearstarch muslin.