WordNet
Usage examples of "seize on".
The leaders of the present system tell them of their rights, as men, to take fortresses, to murder guards, to seize on kings without the least appearance of authority even from the Assembly, whilst, as the sovereign legislative body, that Assembly was sitting in the name of the nation-- and yet these leaders presume to order out the troops which have acted in these very disorders, to coerce those who shall judge on the principles, and follow the examples, which have been guaranteed by their own approbation.
So two things happen: people who've been barred by a eugenics board, feeling they've been unjustly deprived, hide their sour-grapes pose behind a mask of self-righteousness - and a lot of people who can't face the responsibility of raising prodgies seize on this as an excuse to copy them.
I suggest that he should have a weapon, but not one he can seize on his own impulse.
This fortunate circumstance should bring people to one mind, and, with hope thus renewed, let us at once seize on the means of salvation thus presented to us.