unnoble

From Middle English unnoble, equivalent to un- +‎ noble.

unnoble (comparative more unnoble, superlative most unnoble)

1. (dated, chiefly pre 1900) Not of noble rank.

   1800, William Took, View of the Russian empire during the reign of Catharine the Second

   Yet from the commencement of mining there have been unnoble proprietors of mines, who belonged to the class of merchants.

2. Not noble; ignoble; base.
3. (metallurgy) Of a metal, being at the lower end of the electrochemical series, i.e. oxidising readily.

   unnoble metal

• (metallurgy): base, see base metal

• unnobleness

unnoble (third-person singular simple present unnobles, present participle unnobling, simple past and past participle unnobled)

1. (transitive) To make (someone or something) no longer noble

• nonblue