What does "least" mean?

Least: At least, or At the least, at the least estimate, consideration, chance, etc.; hence, at any rate; at all events; even. See However. He who tempts, though in vain, at least asperses The tempted with dishonor. Milton. Upon the mast they saw a young man, at least if he were a man, who sat as on horseback. Sir P. Sidney. -- In least, or In the least, in the least degree, manner, etc. "He that is unjust in the least is unjust also in much." Luke xvi.

Additional senses

  1. 2.-- Least squares (Math.), a method of deducing from a number of carefully made yet slightly discordant observations of a phenomenon the most probable values of the unknown quantities. Note: It takes as its fundamental principle that the most probable values are those which make the sum of the squares of the residual errors of the observation a minimum.
  2. 3.In the smallest or lowest degree; in a degree below all others; as, to reward those who least deserve it.
  3. 4.See Lest, conj. [Obs.] Spenser.

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