verb, seized, seiz⋅ing.| 1. | to take hold of suddenly or forcibly; grasp: to seize a weapon. |
| 2. | to grasp mentally; understand clearly and completely: to seize an idea. |
| 3. | to take possession of by force or at will: to seize enemy ships. |
| 4. | to take possession or control of as if by suddenly laying hold: Panic seized the crowd. |
| 5. | to take possession of by legal authority; confiscate: to seize smuggled goods. |
| 6. | Also, seise. Law. to put (someone) in seizin or legal possession of property (usually used in passive constructions): She was seized of vast estates. |
| 7. | to capture; take into custody. |
| 8. | to take advantage of promptly: to seize an opportunity. |
| 9. | Nautical. to bind or fasten together with a seizing. |
| 10. | to grab or take hold suddenly or forcibly (usually fol. by on or upon): to seize on a rope. |
| 11. | to resort to a method, plan, etc., in desperation (usually fol. by on or upon): He must seize on a solution, however risky. |
| 12. | to have moving parts bind and stop moving as a result of excessive pressure, temperature, or friction (usually fol. by up): The engine seized up from cold. |

seize on
Also, seize upon.
Grab or take hold of suddenly, as in He seized on the bell rope and started to pull vigorously, or She seized upon every opportunity to present her side of the story. [Late 1600s]
Resort to some action, especially out of dire necessity, as in He seized upon any excuse, no matter how farfetched.