ḤUMRA (Aramaic חֻמְרָא "severity or sternness"), a legal term in talmudic and halakhic literature applied to the stricter and more severe of two possible rulings in doubtful cases of ritual law and observance. The opposite of ḥumra is kulla (קֻלָּא), meaning the more lenient and permissive approach. In tractate Eduyyot, chapters 4 and 5, the Talmud gives a complete list of the ḥumrot and kullot, i.e., the more restrictive and the more lenient decisions of the academies of *Hillel and *Shammai. In doubts regarding biblical law the stricter ruling should be followed, whereas in matters of rabbinic laws and ordinances the more lenient solution may be adopted. In later usage, the term also referred to the restrictions that pious individuals voluntarily imposed upon themselves in ritual observance which was over and above the requirements of the law.
Eisenstein, Yisrael, 5 (1911), 272–3.