Sajʿ requires correspondence at the terminal letter, not identity of the two words’ lexical roots. Its final-letter criterion differs from the detailed comparison of letter type, number, vocalization, and sequence used to classify forms of jinas.
The recited or spoken ending, including pauses, can affect the audible pattern; written spelling alone does not settle every question about phonetic correspondence.
Once terminal correspondence is recognized, the relative word patterns and possible matching internal expressions determine whether the form is muṭarraf, muraṣṣaʿ, or mutawāzī.