vera is a text database of acronyms available at gnu.org. It would be pretty easy to take the initial character of your candidate acronym, lowercase it and search the vera.? file for a match.

my $meaning;
if ( /\b([A-Z]?)\b/ ) {
    open my $fh, '<', '/path/to/vera/vera.' . lc( substr $1, 0, 1)
        or die $!;
    while (<$fh>) {
        $meaning = <$fh> and last if /$1/;
    }
}
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If you want to do a lot of that, it would probably pay to set up a simple database of the vera data. Perl can do that for you, too.