v. To declare earnestly, seriously, or positively; to affirm.
the GNU version of the Collaborative International Dictionary of English
v. To affirm or aver positively, or with solemnity.
The Century Dictionary and Cyclopedia
To affirm or aver positively, or with solemnity.
Synonyms Assert, Affirm, Declare, etc. (see assert); to say, allege, protest, insist, maintain.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
v. state categorically
Word Usage
"What I asseverate is, that his Excellency, having the same intercourse with his horse during his exercise, that he hath with his soldiers when training them, may form and break either to every feat of war which he chooses to practise, and accordingly that this noble charger is admirably managed."