Yet Another Boring Meeting (where when I'm not needed, I hack Perl). Here's the capture you need. Note that it was quick and dirty, so I have not inserted any checking at all (which should be promoted; always check the value of a capture):

use v5.12;
use warnings;

my $Namelist = 'Wilma Fred Barney Betty Dino';

if ( $Namelist =~ m/(\w+a)/) {
    print "Matched|$<$&>$|\n";
    say "The name that matched was $1 \n";
} 
else {
    print "No match: \n";
}
[download]

Output:

spek@scelia ~/scratch $ perl format.pl
Matched|1000Wilma>0
The name that matched was Wilma
[download]