What does anneal mean?
To anneal is to subject a material — most often metal or glass — to carefully controlled heating followed by slow cooling, a process that relieves internal stresses and transforms a brittle substance into one that is tough, durable, and easier to shape. In workshops and laboratories alike, annealing is a deliberate act of patience: rushing the cooling defeats the purpose, since rapid cooling produces hardness at the cost of fragility. The word also carries a respected figurative life, describing character or resolve that has been strengthened, rather than broken, by prolonged trial — as when hardship is said to have annealed someone's determination. Rooted in Old English, where it originally meant simply to set alight, the term was gradually adopted by craftsmen for the fires of their trade. Today it belongs chiefly to the vocabulary of engineering and materials science, though its metaphorical reach makes it a quietly powerful word in everyday prose.
verbTo heat a material, especially metal or glass, and then cool it slowly in order to make it tougher, less brittle, and easier to work; more broadly, to strengthen or toughen something through a controlled process.
- To heat metal, glass, or another material and cool it slowly to reduce brittleness and internal stress, making it tougher and easier to work.
- More broadly, to strengthen or toughen something through a gradual, controlled process (used figuratively).
"The blacksmith annealed the blade slowly in embers so it would hold its edge without shattering."
"The glassblower annealed each vase overnight in the kiln to keep it from cracking."
"Years of quiet hardship had annealed her resolve into something unbreakable."
The word 'anneal' began life meaning simply 'to set on fire' — centuries before metallurgists turned that fiery past into a byword for careful, strengthening heat.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of anneal
Anneal descends from the Old English verb onælan, which meant to set on fire or kindle, formed from a prefix plus ælan, a verb connected with burning. Over the Middle English period the word's sense narrowed from general burning to the craftsman's practice of heating and slowly cooling metal to toughen it, giving the modern technical meaning. Its history is thus a striking case of a word of fiery origin being tamed into a term for controlled, strengthening heat.
Related word forms
How anneal is actually used
Primarily a technical term in metallurgy, glassmaking, and materials science, where specific annealing procedures have precise industrial names; figurative use in general writing is less common but well established. The noun sense (an act or result of annealing) exists but is rare outside specialist contexts.
Easily confused with anneal
Annals are chronological historical records, while anneal is a verb meaning to heat and cool a material to toughen it — the two merely sound alike.