grammar - function of the particle も in 「~も辞さない」

I came across the sentence「訴訟も辞さない」in a book today and even though I am able to understand its meaning, I can't figure out the actual function of も in this case.

I looked into my grammar dictionary and the most satisfying definition I got was "も: a marker which indicates emphasis", but I'm not convinced it's the right one.

Should I just think it as a whole with 「辞さない」？　I know it's a phrase used to express one's willingness to do something, but is it used with any other particle ?

Thank you for you answers in advance.

Also, I can provide context if needed.

Answer

I think the も here is this:

1⃣ 係助詞 3-㋑動詞の連用形や動作性名詞に付き、打消しの語と呼応して、強い否定の意を表す。「思いもよらぬ話」「返事もしない」(デジタル大辞泉)

So the も indicates emphasis, used with a negative phrase.

I think this も is usually translated as "even":

• 訴訟を辞さない wouldn't hesitate to file a lawsuit; willing to bring a lawsuit


• 訴訟も辞さない wouldn't even hesitate to file a lawsuit; willing to bring even a lawsuit