Note for Definition 1: From E-NED:
The name for a devil said to collect fragments of words dropped, skipped, or mumbled in the recitation of divine service, and to carry them to hell, to be registered against the offender.
Hence, a name for a demon or devil in the mystery plays.
Also found in France and Germany, 13–15th centuries.
Also see Michael Quinion's World Wide Words
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from medieval Latin Tuti-, Titivillus, in Old French also Tutiville: of unknown origin.
Connection has been suggested with Latin tītivillitium used once by Plautus, and inferred to mean ‘a mere trifle, a bagatelle’.
But in some of the earliest continental instances of the name, it is written Titinillus, or Tutinillus, and in many it is impossible to say whether the middle consonant is n or u (v).
At an early date English usage settled on u (later v and f).
Titivillus was evidently in origin a creation of monastic wit, but in its English form the name passed from the Mystery Plays into popular speech as a term of the vernacular, still in use after 1600.
From: The Proverbs, Epigrams, and Miscellanies of John Heywood
Edited by John S. Farmer, 1906
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