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The dictionary · Word parts

micro-

MY-kroh prefix

A word beginning that means very small; in units, one millionth.

micro- means

small

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What it means

The beginning of words for things too small to see or tiny in size. A microscope lets you see microorganisms such as bacteriumbak-TEER-ee-umA tiny one-celled living thing, seen only under a microscope, of which some kinds cause disease; the plural is bacteria.Full entry ; microcephaly is a smaller-than-normal head; a microbe is a tiny living thing. In measurement, a microgram (mcg) is one millionth of a gram, a thousand times smaller than a milligram.

For the nurse

Write "mcg" for microgram. The symbol µg is on ISMP's error-prone list because it can be misread as mg, a thousandfold overdose.

At a glance
Also written
micr-
Filed under
Word parts

Words built from micro-

Every word in this dictionary built from it, the part marked in each.

microbeMY-krohb

A living thing too small to see without a microscope, such as a bacterium, fungus or parasite; viruses are often included.

antimicrobialan-tee-my-KROH-bee-ul

A drug or substance that kills or slows the growth of microorganisms such as bacteria, viruses, fungi or parasites.

microorganismmy-kroh-OR-guh-niz-um

A living thing too small to see without a microscope, such as a bacterium, virus, fungus or parasite.

micronutrientMY-kroh-NOO-tree-ent

A vitamin or mineral that the body needs in small amounts to work and grow normally.

microbiologymy-kroh-by-OL-uh-jee

The study of microorganisms such as bacteria, viruses, fungi and parasites; also the lab that tests for them.

microdebridermy-kroh-dih-BRY-der

A powered handpiece with a rotating blade that cuts small pieces of tissue and suctions them away at once.

microvillimy-kroh-VIL-eye

Microscopic, fingerlike projections on the surface of a lining cell, as in the small intestine, that together form the brush border.

Words that go with it

Read these next: they turn up in the same notes, orders and questions.

-scopeskohp

A word ending that means an instrument for looking or examining.

Instruments that go with micro

Real photos of each one, the names techs call it and what it’s for. Tap one to see it up close.

Dedo Laser Micro LaryngoscopeViewing · On 1 setup Micro Injection NeedleCutting & Dissecting Micro RetractorRetracting Micro ClampClamping & Occluding · On 2 setups Jacobson Micro ForcepsGrasping & Holding Cooley Micro Needle HolderSuturing Micro Kitzmiller ClampClamping & Occluding Devgan Micro Capsulorhexis Cystotome Scissor-Action ForcepsGrasping & Holding Micro ForcepsGrasping & Holding · On 1 setup Microspike Approximator ClampClamping & Occluding Micro-fracture Chondral PickCutting & Dissecting Lieberman MicrofingerAccessory
How a word looks in a practice question

A client’s heart rate is 128 beats per minute an hour after surgery. Which finding is the most likely cause of the tachycardia?

A. A urine output of 50 mL/hrB. A blood pressure of 88/50 mm HgC. A temperature of 37.0 °C
tachycardiatak-ih-KAR-dee-uh

A heart rate faster than normal; in an adult, more than 100 beats per minute.

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In practice questions

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