Q:

What does "strident note" mean?

so I'm translating an RPG book from English to Brazilian Portuguese and stumbled upon (for the first time) with the expression "strident note". I'm not familiar with it, and although I can sort of grasp the overall idea of the excerpt where it appears, I wanted to have a better understanding of its meaning, but my attempts to google it returned no results with its meaning, just examples of usage.
Can anyone help me? Here's the excerpt:

"Ana's ultimate goal is to persuade her husband to use his authority
  to have the cigani identified as an undesirable pagan influence on
  [...]. Unfortunately, Father Filopovic is a more tolerant man than she
  had anticipated, and a strident note has entered her calls to
  eject the cigani."

A:

A literal strident sound is one that is "loud, unpleasant, and rough"; figuratively the term can be used about something expressed in forceful language that does not try to avoid upsetting other people. Ana's efforts to have the cigani identified as a pagan influence (etc) were not as successful as she had hoped, so she used forceful, possibly impolite, language in calling for their ejection.
https://dictionary.cambridge.org/dictionary/english/strident

