【Secure】 ,  【anchor】 ,  【moor】 ,  【rivet】  can all in extended use mean to fasten or fix firmly or immovably.

They are, however, not often interchangeable because of implications derived from their primary senses.

One secures something that may get lost, may escape, or may permit invasion or intrusion if allowed to remain loose or to work loose; the word usually implies care or protection as the end of the action.

One anchors or moors something unstable or subject to tugging or pulling by external forces or influences to another thing strong enough to hold it down or in place or powerful enough to counterbalance or counteract the opposing forces.

But  【moor】 , which in its primary sense implies a making fast between two anchors or two or more lines or cables, may in extended use suggest greater steadiness or an even balancing of forces that make for stability.

One rivets one thing to another when one joins things normally or actually separate from each other as closely together as though a 【rivet】 had been driven through them.