Is it farther or further?
"very small amount," 1630s, figurative use of iota, ninth and smallest letter in the Greek alphabet. Modern use is after Matt. v:18 (see jot), but iota in classical Greek also was proverbially used of anything very small. The letter name is from Semitic (cf. Hebrew yodh).
The Greek letter iota. Entries beginning with this character are alphabetized under iota.
iota i·o·ta (ī-ō'tə)
Symbol ι The ninth letter of the Greek alphabet.