#!/usr/bin/env perl
use strict;
use warnings;
use Data::Dumper;

my %dic;

while (<DATA>) {
    chomp;
    my($columnA, $columnB) = split("\t", $_);
    $dic{$columnA} = $columnB;
}
print Dumper \%dic;

my $regex = join ( "|", map {quotemeta} sort { length $a <=> length $b } keys %dic ); 
   $regex = qr/(?<!\w)($regex)(?=\s|$)/;
print $regex;

my $sentence = "this word word (word) is a word\n";
$sentence =~ s/$regex/$dic{$1}/g; 
print $sentence;

__DATA__
word word	parola parola
(word)	(parola)