cosmic microwave background

noun

: background radiation

Examples of cosmic microwave background in a Sentence

Recent Examples on the Web

The effects would be especially disruptive in Antarctica, where observatories take advantage of the continent’s remote, dry conditions and the round-the-clock darkness of polar winter to study subtle signals such as the cosmic microwave background. — Arielle Frommer, Scientific American, 20 Aug. 2026

Actually colder than the cosmic microwave background, the faint afterglow of the Big Bang itself. — Kaif Shaikh, Interesting Engineering, 6 Aug. 2026

Penzias and Wilson had accidentally found the cosmic microwave background, or CMB, the leftover radiation from the big bang. — IEEE Spectrum, 20 Jan. 2026

Having established that the cosmic microwave background is symmetric on large scales, variations in this relic radiation from the big bang have been found. — Subir Sarkar, Space.com, 5 Jan. 2026

Word History

First Known Use

1981, in the meaning defined above

Rhymes for cosmic microwave background

• abound
• aground
• around
• astound
• campground
• clothbound
• confound
• earthbound
• eastbound
• expound
• fairground
• foreground