Etymology
From cool + headed, thus "having a cool head."
Adjective
coolheaded (comparative more coolheaded, superlative most coolheaded)
- Having an even temper; calm and collected
1921, Edison Marshall, “The Heart of Little Shikara”, in O. Henry Memorial Award Prize Stories of 1921:There had been none among them coolheaded enough to reason out which trail he had likely taken, and thus look for him by the ford.
1996 August 30, Jeffrey Felshman, “How to Win Enemies and Influence People”, in Chicago Reader:The heated rhetoric masked a more coolheaded strategy.
2007 March 25, Liesl Schillinger, “The Evolution of a City, in Words and Pictures”, in New York Times:Some essays are coolheaded, some shake with hysteria, some are memoirish, others didactic.