Definition of "impressible"

Like other men who have little religion, Mr. Paul Dangerfield had a sort of vague superstition. He was impressible by omens, though he scorned his own weakness, and sneered at, and quizzed it sometimes in the monologues of his ugly solitude.

1863, Sheridan Le Fanu, The House by the Churchyard

The differences of impressible and not impressible; figurable and not figurable; mouldable and not mouldable; scissile and not scissile; and many other passions of matter, are plebeian notions, applied unto the instruments and and uses which men ordinarily practise; but they are all but the effects of some of these causes following, which we will enumerate without applying them, because that would be too long.

1651, Francis Bacon, Sylva Sylvarum