Surreptitious attacks involve picks, bump keys, shims, unauthorized key duplication, and other bypass techniques that, when employed, do not show obvious signs of compromise.

Diplopodia is a congenital anomaly in tetrapods that involves duplication of elements of the foot on the hind limb.

Construction of the new link will involve duplication of the Carlingford Line including a new station to replace the Camellia and Rosehill stations, and upgrades of the remaining stations on the current Carlingford Line.

While the rules do not prevent this, Home Officer Circular 48/1991, para 58 makes it clear that such an arrangement involves unnecessary duplication and should only be allowed in exceptional circumstances.

Chromosomal disorders involve the loss or duplication of larger portions of a chromosome (or an entire chromosome) containing hundreds of genes.

- Note involving normal duplication of heart sounds, etc.

The rail plans also involved significant duplication and quadruplication of existing lines.

Our extraordinary budget is already becoming increasingly costly and covers an increasingly dense network of EU agencies which inevitably involve duplication of effort and overlapping authority.

Many baby talk words for animals involve duplication of the onomatopoeia of the sound they make, including: