seize upon

• seize on

seize upon (third-person singular simple present seizes upon, present participle seizing upon, simple past and past participle seized upon)

1. To grasp or take hold of (an object) suddenly, forcibly, or tightly.

   The child seized upon the cat's tail as soon as it was within reach.

2. To take up, embrace, enact, or turn eagerly to (a plan, idea, ideology, cause, practice, method, etc.); to grasp, understand, and accept quickly; to adopt wholeheartedly or vigorously.

   I heard her ideas and seized upon them immediately.

   The committee seized upon the new plan at once.

   • 1910, Emerson Hough, chapter I, in The Purchase Price: Or The Cause of Compromise, Indianapolis, Ind.: The Bobbs-Merrill Company, OCLC 639762314, page 0105:

     Captain Edward Carlisle, soldier as he was, martinet as he was, felt a curious sensation of helplessness seize upon him as he met her steady gaze, her alluring smile; he could not tell what this prisoner might do.

3. To take possession of or claim (an idea, person, event, etc.) as one's own; to assimilate, absorb, annex, co-opt.

   After the controversy of her public statement, she has been the darling of right-wing groups who have seized upon her as the poster child of their cause.

• (take hold of): fasten on, hook on, latch on

• seize up