The Snib
A snib is a small bolt or latch — a flat bar that slides or pivots to hold a door shut. The word is Scots and Northern English, possibly from Low German or Scandinavian roots. To snib a door is to bolt it from the inside, casually, without a key. The gesture is intimate: a thumb pushes a lever, a bar slides into a socket, and the door is held. Not locked — held. The distinction matters. A lock engages a mechanism: tumblers, pins, springs. A snib engages only itself. It is the simplest possible barrier: a piece of metal that sits in a piece of metal, moved by the nearest hand.
On a Yale-type night latch, the snib is a small button or toggle on the inner face of the lock. Pressing it holds the latch bolt in the retracted position — the tongue stays pulled back into the lock body, and the door can be pushed open from either side without a key. This is snibbing the lock open: converting a locking mechanism into free passage. During the day, the snib is engaged; people come and go. At night, the snib is released; the latch extends and the door locks behind anyone who leaves. The snib does not add security. It subtracts security, temporarily, by the deliberate choice of whoever is inside. It is the mechanism by which a lock admits that it is not always wanted.
On a sash window, the snib is a small pivoting catch mounted on the meeting rail — the horizontal bar where the upper and lower sashes overlap when the window is closed. Turning the snib by thumb locks the two sashes together, preventing either from sliding. It does not strengthen the frame. A firm push from outside would break it. The snib deters rather than resists: it makes the window behave as if it were a single fixed pane rather than two moveable panels. Burglars know that a window snib is a gesture, not a barrier. But the gesture matters. It says the window was closed on purpose and by someone who intended it to stay that way.
Three snibs: a door bolt, a latch toggle, a window catch. Each is a minimal fastener that holds something shut by the decision of the person on the inside. The snib carries no authority. It has no key, no combination, no mechanism that distinguishes between permitted and forbidden entry. It is simply a choice made physical — the smallest possible act of closure, done by hand, undone by hand, and meaningful only because someone chose to throw it.