insouciant
'carefree; careless (unserved)’
Lexical development traced from the Tamil root:
F. insouciant ‘careless, thoughtless, heedless’ < in- ‘not’ + souciant ‘caring’ < soucier ‘to care’ < Lat. solicitare, sollicitare ‘to disturb, rouse, trouble, harass; stimulate, provoke’ < sollicitus ‘agitated’ < sollus ‘whole, entire’ + citus ‘aroused’ < soo < sol- < Tamil iṟai