month of Sundays

month of Sundays  {n. phr.},  {informal}

Очень долгое время (~очень давно). — исп. для эмфазы после "for" или "in" и обычно после отрицания.

I have not had devil's food cake in a month of Sundays.

When he got her first letter, he felt that he had not heard from her for a month of Sundays.

Син.: DOG'S AGE.