The vocabulary of Tamil is mainly Dravidian. A strong sense of linguistic purism is found in Modern Tamil, which opposes the use of foreign loan-words. Nonetheless, a number of words used in classical and modern Tamil indicate copying from languages of neighbouring groups, or with whom the Tamils had trading links, including Munda (for example, tavaḷai "frog" from Munda tabeg), Malay (e.g. cavvarici "sago" from Malay sāgu), Chinese (for example, campān "skiff" from Chinese san-pan) and Greek (for example, ora from Greek ὥρα). In more modern times, Tamil has imported words from Arabic, Persian, Urdu and Marathi, reflecting groups that have influenced the Tamil area at various points of time, and from neighbouring languages such as Telugu, Kannada, and Sinhala. During the modern period, words have also been adapted from European languages, such as Portuguese, French, and English.
The strongest impact of purism in Tamil has been on words taken from Sanskrit. During its history, Tamil, along with other Dravidian languages like Telugu, Kannada, Malayalam etc., was influenced by Sanskrit in terms of vocabulary, grammar and literary styles, reflecting the increased trend of Sanskritisation in the Tamil country.Tamil vocabulary never became quite as heavily Sanskritised as that of the other Dravidian languages, and unlike in those languages, it was and remains possible to express complex ideas (including in science, art, religion and law) without the use of Sanskrit loan words.In addition, Sanskritisation was actively resisted by a number of authors of the late medieval period, culminating in the 20th century in a movement called taṉit tamiḻ iyakkam (meaning "pure Tamil movement"), led by Parithimaar Kalaignar and Maraimalai Adigal, which sought to remove the accumulated influence of Sanskrit on Tamil. As a result of this, Tamil in formal documents, literature and public speeches has seen a marked decline in the use Sanskrit loan words in the past few decades, under some estimates having fallen from 40–50% to about 20%. As a result, the Prakrit and Sanskrit loan words used in modern Tamil are, unlike in some other Dravidian languages, restricted mainly to some spiritual terminology and abstract nouns.
In the 20th century, institutions and learned bodies have, with government support, generated technical dictionaries for Tamil containing neologisms and words derived from Tamil roots to replace loan words from English and other languages.
Words of Tamil origin occur in other languages. Popular examples in English are cheroot (curuṭṭu meaning "rolled up"), mango (from mangai), mulligatawny (from miḷaku taṉṉir meaning pepper water), pariah (from paraiyan), curry (from kari), and catamaran (from kaṭṭu maram, கட்டு மரம், meaning "bundled logs"),pandal (shed, shelter, booth), tyer (curd), coir (rope). Tamil words are also found in Sinhala and Malay.