\Pre*sump"tion\ (?; 215), n. [L. praesumptio: cf. F.
pr['e]somption, OF. also presumpcion. See {Presume}.]
1. The act of presuming, or believing upon probable evidence;
   the act of assuming or taking for granted; belief upon
   incomplete proof.
2. Ground for presuming; evidence probable, but not
   conclusive; strong probability; reasonable supposition;
   as, the presumption is that an event has taken place.
3. That which is presumed or assumed; that which is supposed
   or believed to be real or true, on evidence that is
   probable but not conclusive. ``In contradiction to these
   very plausible presumptions.'' --De Quincey.
4. The act of venturing beyond due beyond due bounds; an
   overstepping of the bounds of reverence, respect, or
   courtesy; forward, overconfident, or arrogant opinion or
   conduct; presumptuousness; arrogance; effrontery.
         Thy son I killed for his presumption. --Shak.
         I had the presumption to dedicate to you a very
         unfinished piece.                     --Dryden.
{Conclusive presumption}. See under {Conclusive}.
{Presumption of fact} (Law), an argument of a fact from a
   fact; an inference as to the existence of one fact not
   certainly known, from the existence of some other fact
   known or proved, founded on a previous experience of their
   connection; supposition of the truth or real existence of
   something, without direct or positive proof of the fact,
   but grounded on circumstantial or probable evidence which
   entitles it to belief. --Burrill. --Best. --Wharton.
{Presumption of law} (Law), a postulate applied in advance to
   all cases of a particular class; e. g., the presumption of
   innocence and of regularity of records. Such a presumption
   is rebuttable or irrebuttable.