English Reference

Word

millimeter

Phoneticsmil·lime·ter

/ˈmɪɫəˌmitɝ/

UK spelling · millimetre

Definition

n. a very small unit of length. There are ten of these in one centimeter and one thousand in a meter.

n. a metric unit of length equal to one thousandth of a meter. Often used for precise measurements in technical or scientific contexts.

Examples

“The insect is only one millimeter long.”

“The carpenter measured the gap carefully to ensure it was within a millimeter of the plan.”

“Modern manufacturing requires components to be machined with a tolerance of less than a millimeter to ensure the mechanical parts fit together perfectly.”

Examples

simple

“The insect is only one millimeter long.”

contextual

“The carpenter measured the gap carefully to ensure it was within a millimeter of the plan.”

complex

“Modern manufacturing requires components to be machined with a tolerance of less than a millimeter to ensure the mechanical parts fit together perfectly.”

Usage

Commonly abbreviated as 'mm' in both technical and everyday writing.

Pitfall

ten millimeter

ten millimeters

When used as a noun with a number greater than one, it must be plural; the singular form is only used when it acts as a modifier before another noun.

Etymology

From French millimètre, as if milli- + meter.

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

Collocations

millimeters off every year

This entry

Level
A2 · Elementary
Frequency
Occasional
Updated

Scan code

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English Reference