What is the meaning of Anneal?

To subject to great heat and then (often slow) cooling, and sometimes reheating and further cooling, for the purpose of rendering less brittle; to temper; to toughen.

To cool glass slowly, to minimize internal stress.

To burn colors onto a glass or other surface.

To make a double-stranded nucleic acid by pairing a single strand with a complementary strand.

To strengthen or harden.

An act of annealing.

Source: wiktionary.org