What is the meaning of Ith?

Occurring at position i in a sequence.

The letter ⟨(⟩, which stands for the th sound (/θ/) in Pitman shorthand.

behind

to follow someone

to eat

corn, grain

second-person singular imperative of ithid

eat

(not in science) particle, atom, a grain

grain, corn.

Source: wiktionary.org