A group who have been mates for a long time. Gender doesn't disqualify people from being part of a squad, but if a group of chicks meet through their boyfriends/husbands then they cannot label themselves a squad in their own right and expect to be taken seriously.
They can only adopt the moniker 'squad wags.'
squad hopeful: The other day me and the squad.....'
True squad: 'Whoa! Easy there sport, get back in your box. You belong to no legitimate squad. Maybe squad wag is more your pace.'