Heatstroke

Part of speech: noun

Definitions

1. A dangerous health condition that occurs due to extreme heat exposure, causing the body to lose its ability to regulate temperature effectively and potentially resulting in severe complications
2. An acute illness arising from prolonged high temperatures affecting the body's thermoregulation, which can lead to critical health issues if untreated
3. A serious medical condition caused by the body overheating in hot environments and failing to cool down properly

Etymology: "Heatstroke" is a plain compound of "heat" and "stroke," and the second half is the more interesting one. "Stroke" comes from Old English "strācian," meaning to stroke or caress, and it was later used for a blow or a sudden attack. The medical sense of "stroke" as a sudden seizure or blow to the body came later, and "heat stroke" follows the same pattern: the heat is imagined as a sudden blow that strikes the body all at once. The word is written both as one word and as two, and the spelling "heat stroke" is the older and more widely accepted form in dictionaries. The single-word spelling is simply a variant of that same compound, with no difference in meaning.

Synonyms: sunstroke, heat exhaustion, heat illness