Adherence or sticking in one place; fixation in a physical sense (attachment or staying in position).
壁紙の端がはがれて定着していない。
The edge of the wallpaper has come loose and isn't sticking.
接着剤で部品を定着させた。
I fixed the part in place with adhesive.
塗装が剥がれて、塗料が定着していない箇所がある。
The paint has peeled off; there are spots where the coating didn't adhere.
Becoming established or taking root (of a custom, system, idea, etc.); to become commonly accepted or ingrained.
リモートワークが会社に定着してきた。
Remote work has begun to become established in the company.
新しい教育制度が徐々に定着している。
The new educational system is gradually taking hold.
その表現は若者の間で定着している。
That expression has become established among young people.
In photography, the process of fixing an image (fixation) to make it permanent during development.
現像の最後に定着を行って写真を保存する。
At the end of development, you fix the image to preserve the photograph.
定着液の濃度が低いと像が十分に定着しないことがある。
If the fixer solution is too weak, the image may not be properly fixed.