1.nounA census, an enumeration, a review, a survey.
2.nounA critical revision of a text.
3.nounA text established by critical revision.
4.nounA family of manuscripts which share similar traits; the variety of a language which is used in such manuscripts.
"The Russian recension of Old Church Slavonic emerged after the 10th century and was characterized by the substitution of /u/ for the nasal sound /õ/."