unmastered

From un- +‎ mastered.

unmastered (not comparable)

1. Not mastered (in various senses).
   • c. 1599–1602 (date written), William Shakespeare, The Tragicall Historie of Hamlet, Prince of Denmarke: […] (Second Quarto), London: […] I[ames] R[oberts] for N[icholas] L[ing] […], published 1604, →OCLC, [Act I, scene iii]:

     Then way what loſſe your honor may ſuſtaine / If with too credent eare you liſt his ſongs / Or looſe your hart, or your chaſt treaſure open / To his vnmaſtred importunity.

unmastered

1. simple past and past participle of unmaster

• mensurated, undermates, unstreamed