Uttaramerur had 12 cheris in the 12 names of Lord Vishnu. Cheri - the term - is not the same as it is today as in olden days. Any small group of settlement was called cheri.
Being a vaishnavite village, Uttaramerur's 12 cheris were named after the 12 manifestations of Lord Vishnu. God is considered as the ultimate but in order for mankind to realize him, he comes down in different forms. These are called Vyuha forms. Below vyuha is the archcha forms which we worship today in all temples.
Concept is from archcha we slowly transcend so that we are mature enough to realize vyuha and slowly the formless form. In other words, what starts out as an object of worship (Icon) vanishes in course of time and a devotee realizes at some point of time that all objects are manifestations of the almighty. It is like a child requiring a cruch to walk in the beginning and in the end it walks on its own - since it realizes that it does not need support anymore.
Hence the vyuha and archcha forms in Hinduism to the best of my knowledge. Learned can correct me.
Lord Vishnu has 12 such forms. Madhava, Madhusooshana, Sankarshana, kesava, Govinda, Hrushikeesa, Damodara, Padmanabha, Naraayana etc
In a given temple, when lord is called by a specific name, it means he is residing in that form in that temple. You might have come across Rishikesh - it is derived from Hrushikesha. Similarly the lord of Tiruvanandapuram is called Padhmanaabha.
Uttaramerur had 12 such cheris - all named after this forms. Kesava cheri, madhavach cheri, Govindhach cheri and so on