Definitions
1.VerbTo assert the truth of (something); to affirm (something) with confidence; to declare (something) in a positive manner.
2.VerbTo justify or prove (an allegation or plea that one has made).
3.VerbTo avouch, prove, or verify the existence or happening of (something), or to offer to do so.
4.NounA beast of burden; chiefly a workhorse, but also a working ox or other animal.
5.NounAn old, useless horse; a nag.