test-tube

1 of 2

adjective

ˈtes(t)-ˌt(y)üb 

1

: in vitro

test-tube experiments

2

: produced by in vitro fertilization

test-tube babies

test tube

2 of 2

noun

: a plain or lipped tube usually of thin glass closed at one end and used especially in chemistry and biology

Examples of test-tube in a Sentence

Recent Examples on the Web

Adjective

After developing into an embryo in a test-tube, it’s implanted into the womb of a female surrogate animal. —Emily Mullin, Wired News, 7 Apr. 2025

National Geographic harnesses some of that tendency in this kit that contains instructions and equipment for 15 different gross experiments with themes like boiling boogers, farting slime, bursting blood cells, eyeballs, and test-tube vomit. —Cheryl Fenton, Parents, 5 Dec. 2024

Noun

In addition to the mouse study, the researchers also confirmed that the protein quickly clung to carbon monoxide in human blood in test tubes. —Sara Novak, Scientific American, 11 Sep. 2025

One test tube study found that Essiac reduced inflammatory markers in inflamed immune cells. —Lindsey Desoto, Health, 31 Aug. 2025

Word History

First Known Use

Adjective

1866, in the meaning defined at sense 1

Noun

1846, in the meaning defined above

Rhymes for test-tube

• boob
• cube
• lube
• rube
• tube
• hypercube
• nanotube
• phototube

Kids Definition

test tube

noun

: a tube of thin glass closed at one end and used especially in chemistry and biology

Medical Definition

test-tube

1 of 2 adjective

1

: in vitro

test-tube experiments

2

: produced by in vitro fertilization

test-tube babies

test tube

2 of 2 noun

: a plain or lipped tube usually of thin glass closed at one end and used especially in chemistry and biology