How to suppress specific bibtex entry (e.g., language) without biblatex package

Question

In Is it possible to suppress a specific field from bibtex .bbl in biblatex? a related question was asked. The following can suppress language field from appearing in the output, when biblatex package is present.

\AtEveryBibitem{\clearlist{language}} % clears language

How to achieve this suppression without biblatex package (i.e., in plain bibtex)? I am using amsplain as bibtex style. The bibtex file is something like this (provided by https://zbmath.org/):

@Article{zbMATH02658504,
    Author = {A. {Einstein}},
    Title = {{Eine Theorie der Grundlagen der Thermodynamik.}},
    FJournal = {{Annalen der Physik, IV. Folge}},
    Journal = {{Ann. der Phys. (4)}},
    ISSN = {0003-3804},
    Volume = {11},
    Pages = {170--187},
    Year = {1903},
    Publisher = {Johann Ambrosius Barth, Leipzig},
    Language = {German},
    Zbl = {34.0962.01}
}

Answer 1

amsplain.bst has

% The extra section to write out a language field was added
% for AMSPLAIN.BST.  Not present in plain.bst.

FUNCTION {format.language}
{ language empty$
    { "" }
    { " (" language * ")" * }
  if$
}

This tests if the language field is empty and does nothing or outputs it in () depending.

So if you make a copy of that file called say xamsplain.bst and use

\bibliographystyle{xamsplain}

and then modify the definition always to do nothing

FUNCTION {format.language}
    { "" }