Loan words in Sri Lankan Tamil came about mostly due contact between colonial powers and the native population. Linguists study a language's lexicon for a number of reasons. Languages such as Tamil with centuries of literature and multi-cultural contact offer the chance to compare the various processes of lexical change. The words of foreign origin or loanwords illustrate those processes: calques, loanwords, the distinction between function words and content words.
Most Portuguese loan words are for items the native population lacked when the encounter happened c. 1505. Some are administrative terms, others are personal usage terms as well as items directly introduced from South America via the Portuguese traders. Most of these words are also shared with Sinhalese language users.
Loanwords from the neighbouring Indo-EuropeanSinhala are quite sparse in Sri Lankan Tamil (as opposed to the large number of Tamil loan words in Sinhala), which is most likely due to the relative isolation of the exclusively Tamil-speaking settlements in the North and East of the island.