Tittle, n.
Etymology: [OE. titel, titil, apparently a dim. of tit, in the sense of small; cf. G. tüttel a tittle, dim. of OHG. tutta teat. Perhaps, however, the same word as title, n.]
A particle; a minute part; a jot; an iota. It is easier for heaven and earth to pass, than one tittle of the law to fail. Luke xvi. 17. Every tittle of this prophecy is most exactly verified. South.
Shades of meaning
Fernald has no entry of its own for tittle; he lists it under particle.
He lists it without comment; the entries above explain its neighbors.