Meanings (ES + gloss)
asegurar
To assert the truth of (something); to affirm (something) with confidence; to declare (something) in a positive manner.
Chiron, the four-legg'd Bard, had both / A Beard and Tail of his own growth; / And yet by Authors 'tis averr'd, / He made use onely of his Beard.
The Devil, I safely can aver, / Has neither hoof, nor tail, nor sting; / Nor is he, as some sages swear, / A spirit, neither here nor there, / In nothing—yet in everything.