מַכְשִׁיר, מַכְשִׁירִין (כָּשֵׁר) 1) preparatory means, preliminary acts. Meg. 7ᵇ מַכְשִׁירֵי אוכל נפש acts preliminary to the preparation of food (as grinding the slaughtering knife &c.). Ib. הוא ולא מַכְשִׁירָיו it says (Ex. XII, 16) ‘that’ (alone may be done), but not its preliminaries. Ib. מ׳ שאפשר וכ׳ acts which might have been done a day before. Erub. 102ᵇ, sq. מ׳ מצוה requirements of a religious act (to be performed on the Sabbath, v. דָּחָה). Sabb. 136ᵃ מ׳ מילה requirements for circumcision. Tosef. Pes. V, 1; Y. Sabb. XIX, 17ᵃ top; a. fr. —2) Makhshirin (things which make an object fit for levitical uncleanness), name of a treatise of the Mishnah and Tosefta, of the Order of Tohăroth.