Mal: തൃശ്ശൂര് tr̥śśūr
‘City of Shiva’ [Trichur] City/District, Kerala
From Mal: tiru ‘eminent’, ’holy’, ‘auspicious’, ‘prosperous’; Siva; peru/pēr, ‘great’, ‘large’; and ūr, ‘town’, ‘city’.
Trichur is an English corruption of Thrissur which is a Malayalam corruption of an original Thiru-Siva-Peru-Ur.
The 2ndC Vadakkumnathan Temple is dedicated to Shiva. It hosts the annual Thrissur Pooram (a temple festival in April-May dedicated to Durga-Kali). This huge 36-hour event features huge numbers of elephants, parasols, drums and fireworks. It is nicknamed ‘the pooram of all poorams’.
Also: (1) The city where there are three Sivas (temples), Tri-Shiva-Peroor — Vadakkunnathan, Asokeswaram and Irattachira; (2) The city with Siva’s name [Mal: peyar, ‘name’].

Thrissur Pooram at Thekkinkadu Maidanam, Thrissur Kerala Tourism