Coolth
The word ‘coolth’ has the opposite meaning of heat/warmth, referring to the condition of having a moderately low temperature – that is the condition of being cool. It can also be used to describe a net loss of heat to a cool body, or the sensation of feeling coolness, ie ‘the fridge gave off coolth’. It can be used as a pairing with "Heat" i.e. you transfer heat into a system or coolth into a system.
The word ‘warmth’ refers to the condition of having a moderately high temperature - that is the condition of being warm. It can also be used to describe the emission of heat by a warm body, or the sensation of feeling that heat ie ‘the fire gave off warmth’.
It is reported that the word ‘coolth’ has been in use since the 1500s, when a Welsh-English dictionary translated ‘oerfel’ meaning cold as ‘coulthe’ in English. It also appears in Seamus Heaney’s poem ‘Bodies and Souls’ from the 2001 ‘Electric Light’ collection in the line: “The older I get, the quicker and the closer / I hear those laboring breaths and feel the coolth”
It is as useful a word in thermodynamics as the word warmth.
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