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Study Dictionary
Tittle
Tittle [EBD]
a point, (Matt. 5:18; Luke 16:17), the minute point or stroke added to some letters of the Hebrew alphabet to distinguish them from others which they resemble; hence, the very least point.
TITTLE [ISBE]
TITTLE - tit'-'-l (keraia (Westcott-Hort, kerea), from keras, "a horn"): A small stroke or mark, specif. on a letter to denote accent, or as a diacritical mark; used only in Mt 5:18 and Lk 16:17. In the first passage it is used in connection with iota, or jot, i.e. the very smallest thing, and in both it refers to the minutiae of the Law. It is well known that the scribes paid the greatest attention to such marks attached to the letters in the Hebrew Scriptures, the Massoretic Text of which abounds in them.See JOT; YODH.
Also see definition of "Tittle" in Word Study