(intransitive, of a steam boiler) To work so that foaming occurs from too violent ebullition, which causes water to become mixed with, and be carried along with, the steam that is formed.
To apply priming to (a musket or cannon); to apply a primer to (a metallic cartridge).
To prepare; to make ready; to instruct beforehand; to coach.
(politics) To challenge an incumbent sitting politician for their political party's endorsement to run for re-election, through running a challenger campaign in a primary election