1. put something into effect
the manager decided to action the proposal
When using the word 'action' as a verb, you are talking about enacting, carrying out, or making something happen. It is normally used when suggestions or proposals have been made about how to do something, especially if changes or policies have been planned and it is now time to put them into place and make them real. You can 'action a proposal', or 'action someone's recommendations', for example. You are more likely to hear this used in a professional context.