Both Uses

rant
in
A Prayer for Owen Meany
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I know that some of the girls have told their parents that I deliver "ranting lectures" to them about the United States; some parents have complained to the headmistress, and Katherine has cautioned me to keep my politics out of the classroom—"or at least say something about Canada; BSS girls are Canadians, for the most part, you know."†
p. 327.1 *

ranting = complaining or verbally attacking in a loud, excited way
In short, I was doing my best to be a Canadian; I wasn't ranting my head off about the goddamn U.S. this or the motherfucking U.S. that!†
p. 465.3

Definitions:

(1) (rant)
to complain or verbally attack in an excited rather than thoughtful way
(2) (meaning too rare to warrant focus)