Seize/siːz/ Definition 1 of 5Pro Tip 1/3Immediate Action Used when someone takes instant action without hesitation. When he saw the child running towards the road, he seized her hand. Pro Tip 2/3Physical Interaction Often implies physically grabbing or holding something or someone. During the arrest, the officer seized the suspect by the jacket. Pro Tip 3/3Assertiveness Symbolizes taking charge of an opportunity or situation firmly. She seized the opportunity to speak with the CEO at the event.