Kēśirāja, also spelled Keshiraja (Kannada: ಕೇಶಿರಾಜ), was a 13th-century Kannada grammarian and a poet. He is particularly known for authoring Shabdamanidarpana, an authoritative work on Kannada grammar. According to Dravidian scholar Sheldon Pollock, because of this work, he is considered the "greatest theorist of Kannada grammar". He was also a scholar in Sanskrit as well and a court poet (Aasthaana kavi) in the Hoysala Court.
Kesiraja was born in a literary family, comprising several, well-known Kannada writers. His father, Mallikarjuna (C. 1245 CE), was a Kannada poet and brother-in-law of Janna. Kesiraja is also the grandson on his mother's side of another poet, Śankara (Sumanōbana), who was priest of the Yadava capital and poet laureate to King Narasimha I. In some of his works, Kesiraja has called himself Kesava.
Shabdamanidarpana (Kannada: ಶಬ್ದಮಣಿದರ್ಪಣ), ("Jewel-mirror of Grammar") was authored by Kesiraja in 1260 CE. This work remains a comprehensive, authoritative work on Kannada grammar. The rules mentioned therein were penned in kanda metre and followed a vrutti style (illustrative commentary by the author himself). And though Kesiraja followed the model of Sanskrit grammar of the Katantra school and that of earlier writings on Kannada grammar, his work has an originality of its own.
The text of Shabdamanidarpana begins with poetry of earlier generations who are cited by Kesiraja as authoritative examples:
The expert way (sumārgam) of Gajaga, Gunanandi, Manasija, Asaga, Candrabhatta, Gunavarma, Srivijaya, Honna (Ponna), Hampa (Pampa), Sujanōttamsa – these provide the illustrative instances (lakshya) in this work. In Shabdamanidarpana, about twenty poets and 30 different works are cited, and almost every rule is explained with quotations. This work points out the Kannada language development through the preceding three centuries.—Kesiraja (translated)
An attempt at vocabulary building is provided in several parts of the work. There is a list of verbal roots and words containing ḷ and ḹ sounds. There is also a chapter called "PrayŌgasāra" where Kesiraja has quoted a number of rare words along with their meanings.
Passion for grammar
Kesiraja had an interest in grammar, which is evident from his writings through his grammar work Shabdamanidarpana.
Through grammar (correct) words originate; through the words of that grammar, meaning (originates); through meaning the beholding of truth; through the beholding of truth, the desired final beatitude; this (final beatitude) is the fruit for the learned.— sūtra 10 of the Preface, Shabdamanidarpana – Kesiraja 
Apart from his extant grammar work Shabdamanidarpana, Kesiraja authored several other works in Kannada, though they are deemed lost:
- Prabodhachandra (ಪ್ರಬೋಧಚಂದ್ರ)
- Chorapalaka Charitam (ಚೋರಪಾಲಕ ಚರಿತ)
- Kiratam (or Kiratarjuniyam) (ಕಿರಾತ)
- Shubhadraharana (ಸುಭದ್ರಾ ಹರಣ)
- Sri Chitramale (ಶ್ರೀ ಚಿತ್ರಮಾಲೆ)
- Sheldon Pollock (2003). Literary cultures in history: reconstructions from South Asia. Berkeley: University of California Press. p. 364. ISBN 0-520-22821-9.
- E.P. Rice (1982), pp. 44–45
- ""Chapter 6: Chalukyas of Badami"".
- "History of the Kannada Literature -III". Dr. Jyotsna Kamat. Retrieved 2008-05-01.
- E.P. Rice – pp 111
- Sastri (1955), p359
- Sahitya Akademi (1988), p. 1476
- Lexicography in India : Proceedings of the First National Conference on Dictionary Making in Indian Languages, By Bal Govind Misra, page 82
- A Grammar of the Kannada language in English, Ferdinand Kittel – pp. 4