Definition:
The word "fastened" is the past tense of the verb "fasten." It means to attach or secure something tightly so that it stays in place. When something is fastened, it is not loose; it is held together firmly.
As a Verb:
As an Adjective:
Fasten (something) down: To secure something to prevent it from moving.
Fasten (one's) seatbelt: A common phrase used to tell someone to buckle their seatbelt for safety.
"Fastened" describes something that is securely attached or closed. You can use it to talk about securing items like clothing, bags, or safety equipment.