Pillai

Pillai can mean: 
Pillai (Kerala title), a title used in Kerala
Pillai (title), a suffix used by various social and religious groups of South India and Sri Lanka (includes a list of people with this title)
Pillai of Pallichal, a title of the order of nobility in Travancore
Pillai (community), a community from the Indian state of Tamil Nadu and Sri Lanka
Pillai (surname)
Pilai, a Finnish bagpipe
 The Pillai statistic used in multivariate statistics, named after K. C. Sreedharan Pillai
The Indian mathematician Subbayya Sivasankaranarayana Pillai