my @array = qw/ a list of words /;
print "yep, it's there"
  if !!grep { $_ eq "of" } @array;

__output__

yep, it's there

##</code><code>##

my @array = qw/ a list of words /;
print "yep, it's there"
  if "of" =~ /\b (?: ${\join('|', @array) }) \b/x;

__output__

yep, it's there