Step 1: Understanding the term 'Kudirai Chettis'.
In Tamil, the word “Kudirai” means “horse” and “Chetti” refers to traders or merchants. Hence, the literal meaning of “Kudirai Chettis” is “Horse Traders.”
Step 2: Role in Vijayanagara Empire.
The Vijayanagara Empire relied heavily on cavalry in warfare. Since horses could not be bred in large numbers in India, they were imported. Kudirai Chettis were a community of traders who played a crucial role in importing and supplying horses, often through Arabian and Portuguese traders.
Step 3: Conclusion.
Thus, the Kudiraichettis of Vijayanagara were known as “Horse Traders.”
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\boxed{\text{Correct Answer: Horse traders}}
\]