What does shim mean?
A shim is a thin piece of material inserted between two surfaces to fill a gap, distribute pressure, level an object, or prevent unwanted movement. It may be made from metal, wood, plastic, or another suitable material. The term is especially common in construction, woodworking, machinery, and equipment repair, where even a very small discrepancy can cause a door to scrape, a panel to vibrate, or a component to sit incorrectly. As a verb, to shim means to make such an adjustment, usually by inserting a shim or carefully altering the position of a part. Although the word may sound unusual, shims are practical, inexpensive solutions to common alignment and stability problems. The related verb is less common in everyday speech and is most likely to appear in technical or professional contexts.
A thin piece of material used to fill a small gap, level a surface, hold parts in position, or prevent movement.
"A small metal shim made the shelf level."
Common in construction, woodworking, mechanical, and repair contexts.
To fit, support, or adjust something using a shim or by making a slight positional correction.
"The technician shimmed the engine mount to reduce vibration."
Usually used in technical or professional contexts; it typically implies a small adjustment.
The plural is used when referring to multiple thin pieces used for adjustment or support.
"The technician inserted two shims beneath the bracket."
A tiny shim can solve a surprisingly large problem: it can silence a rattling door, stabilize a wobbly table, or make two parts fit together.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does shim come from?
The exact origin of shim is uncertain. The word appears in English in the nineteenth century and is historically associated with shimmy, although the precise relationship between the two forms is not entirely clear. Modern usage developed around the physical sense of a thin piece inserted to adjust or support something.
Related word forms
How shim is actually used
The noun is commonly used in technical, construction, mechanical, and repair contexts. The verb is more specialized and often implies a small, precise adjustment.
Easily confused with shim
A shim is a physical piece used to fill, level, or support a gap, while to skim means to remove a layer from a liquid or to read quickly.