In the following quotation, what is the meaning of "tooth and nail," and what type of
literary expression is this?
“I would not fight publicly for Atticus, but the family was private ground. I
would fight anyone from a third cousin upwards tooth and nail.” (p. 90)

If you will “fight tooth and nail”, it means you will put everything into it - like a mountain lion fighting! Or a Wolf fighting, TOOTH (teeth) and NAIL (claws). She didn’t fight because of her father’s wishes in public but at home - lookout! She would fight like a wildcat!

Explanation:

each morning i wrote my name

on the dusty cabinet, then crossed

the dining table in script, scrawled

in capitals on the backs of chairs,

practicing signatures like scales

while mother followed squirting

linseed from a burping can

on apex:

removing american indians from the south is for their own good.