The Collaborative International Dictionary
Synteresis \Syn`te*re"sis\, n. [NL., fr. Gr. ? preservation, fr. ? to preserve; sy`n with + ? to guard.]
(Med.) Prophylaxis. [Obs.]
(Metaph.) Conscience viewed as the internal repository of the laws of duty.
--Whewell.
Wiktionary
n. (context theology historical English) An aspect of one's conscience by which one can judge wrong from right and decide on what makes good conduct (as distinguished from (term: syneidesis)).
Usage examples of "synteresis".
But laws, on the contrary, since they are only human enactments for the regulation of social life, or the yokes of princes thrown over the necks of their subjects, refuse to be brought to the standard of synteresis, the origin of equity, because they feel that they possess more of arbitrary will than rational judgment.