Thomas Davidson,
Chambers's Twentieth Century Dictionary 1908…
(1908)
“ Eat its head off, used of an animal which costs as much for food as it is worth; Eat one's heart, to pine away, brooding over misfortune; Eat one's terms, to study for the bar, with allusion to the number of times in a term that a student must dine in the hall of an Inn of Court ”
