# Waldo

/ˈwɑɫdoʊ/ (US) · CEFR C2 · Noun

Source: https://englishreference.com/word/waldo
Updated: 2026-08-15

## Definition

a remote-controlled mechanical arm or tool that mimics the movements of a human operator. You use this when you need to handle dangerous materials or work in tight spaces from a distance.

For teachers: a remote-controlled mechanical device, such as a robotic arm, that replicates the precise movements of a human hand or limb. Named after a 1942 science fiction story, it is now a standard term in robotics and nuclear engineering.

## Examples

- The technician uses a waldo to handle the radioactive samples.
- By manipulating the master controls, the surgeon can guide the waldo with extreme precision during the procedure.
- The development of the waldo allowed researchers to interact with hazardous environments from behind lead-shielded glass, translating human dexterity into mechanical action without exposing the operator to radiation.

## Usage notes

- Often used in technical or science fiction contexts; frequently lowercase, though occasionally capitalized in reference to its literary origin.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.