English Reference
noun · verb

shim

n. · v.
US /ˈʃɪm/ UK /ʃˈɪm/ shim UK spelling shims

  1. 01 C1 Advanced Technical

    n.a thin piece of wood, metal, or plastic used to fill a small gap or make something level.

    n.a thin, often tapered piece of material used to fill small gaps, provide support, or ensure precise alignment between components.

    Simple

    The carpenter used a small wooden shim to stop the table from wobbling on the uneven floor.

    In context

    The technician inserted a stainless steel shim to achieve the precise clearance required for the high-speed turbine assembly.

  2. 02 C1 Advanced Technical Computing

    n.a small piece of software that helps an old program run on a new system by fixing compatibility issues.

    n.a small library that transparently intercepts API calls and changes the arguments or handles the operation itself to provide compatibility.

    Simple

    We had to install a shim so the old database software could talk to the new operating system.

    In context

    The developers implemented a polyfill shim to ensure that modern JavaScript features would function correctly in legacy web browsers.

    wrapperadapterpolyfill
  3. 03 C1 Advanced Technical

    v.to use thin pieces of material to make something level or fit perfectly.

    v.to adjust, level, or align a mechanical assembly by the insertion of shims.

    Simple

    You might need to shim the door frame if the wall isn't perfectly straight.

    In context

    The installation crew spent hours shimming the heavy machinery to ensure it was perfectly level before bolting it to the concrete pad.

    Usage

    Often used as a transitive verb taking the object being leveled.

  4. 04 C2 Proficiency Technical

    n.a very thin device that criminals hide inside a credit card reader to steal information.

    n.a paper-thin electronic device inserted into a card-reading slot to intercept data from the chip of a credit or debit card.

    Simple

    The bank warned customers to check the ATM for a shim before inserting their cards.

    In context

    Unlike bulky skimmers, a shim is thin enough to reside entirely inside the card slot, making it nearly impossible for a casual user to detect.

    skimmer

Etymology 1

Unknown; from Kent. Originally a piece of iron attached to a plow; sense of “thin piece of wood” from 1723, sense of “thin piece of material used for alignment or support” from 1860.

Etymology 2

Blend of she + him.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level C2 · Proficiency
Frequency Occasional
Updated