-isha

Swahili

Alternative forms

-lisha/-lesha

Etymology

Uncertain. Nurse & Hinnebusch^[1] mention that correspondences of this suffix within the Sabaki languages are not regular. This implies it was a local innovation, and similar suffixes in other Bantu languages (Chichewa -itsa/-etsa, Yao (Africa) -isya/-esya, Rwanda-Rundi -īsha/-ēsha) are not cognate, but may be parallel developments.

Still according to Nurse & Hunnebusch,^[2] this suffix originated from a causative (with -ya) of the stative (-ik-/-ek-), with spirantization of the -k- to -sh-.

Suffix

-isha (mid vowel harmony variant -esha)

causative suffix
1. (added to a verb) to cause to, to make
  Near-synonyms: -ya, -iza/-eza
  
  ‎-la (“to eat”) + ‎-isha → ‎-lisha (“to feed”)
  
  ‎-weza (“to be able”) + ‎-esha → ‎-wezesha (“to enable”)
2. (added to an adjective) to cause to become, to make
  ‎imara (“strong”) + ‎-isha → ‎-imarisha (“to strengthen”)
3. (added to a noun) to give a characteristic of, to turn into
  ‎sababu (“cause”) + ‎-isha → ‎-sababisha (“to cause”)
  
  ‎orodha (“list”) + ‎-esha → ‎-orodhesha (“to list”)

Derived terms

Swahili causative verbs

References

^ Nurse, Derek; Hinnebusch, Thomas J. (1993), Swahili and Sabaki: A Linguistic History, Berkeley and Los Angeles, California: University of California Press, →ISBN, page 371
^ Nurse, Derek; Hinnebusch, Thomas J. (1993), Swahili and Sabaki: A Linguistic History, Berkeley and Los Angeles, California: University of California Press, →ISBN, page 129

[1] Nurse, Derek; Hinnebusch, Thomas J. (1993), Swahili and Sabaki: A Linguistic History, Berkeley and Los Angeles, California: University of California Press, →ISBN, page 371

[2] Nurse, Derek; Hinnebusch, Thomas J. (1993), Swahili and Sabaki: A Linguistic History, Berkeley and Los Angeles, California: University of California Press, →ISBN, page 129

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