Other forms: fine-tuning, fine-tuned, fine-tunes
To fine-tune something is to make tiny adjustments until it works perfectly. The big decisions are already made; this is the last two per cent.
The image is a radio dial being nudged until the hiss disappears, and the word keeps that sense of small, careful movements. You fine-tune an engine, a recipe, a speech, a set of rules. It always implies the thing already broadly works, which is what separates fine-tuning from fixing. In machine learning it has become a technical term for taking a trained model and adjusting it on a narrower set of data, and that use is now everywhere.
Practised in A Man Called Ove
First appears in chapter 11 of A Man Called Ove.
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