(n.) a hot fire that burns without flames; a secret burning romance or affair
On Valentine’s Day the Scots word greeshoch popped up on HH—defined as both “a fire that burns hot without flames” and, figuratively, “a secret burning romance or warm affection”.
Etymologically, that’s a Scots corruption of the Gaelic word grìosach, meaning “ember” or more loosely, “fireside” or “fireplace”. That word in turn comes from the Gaelic for “fire”, grìs—which is itself the origin of another Scots word, greesh, for a stone platform or mantel that allowed a fireplace to be positioned further forward than the chimney flue above it.
The Scottish National Dictionary dates greeshoch no further back than the early nineteenth century, and like seemingly all Scots dialect words it was used at least once by Sir Walter Scott, in a collection of Scottish minstrelry dating from 1802.
That date would suggest it was in use locally earlier than the SND suggests, and from there the figurative use of greeshoch to mean “a secret burning romance” emerged in the 1820s.