# Galileo

/ˌɡæɫəˈɫeɪoʊ/ (US) · CEFR B2 · Noun

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

## Definition

a famous Italian scientist from the 1600s who studied the stars and planets. He is best known for using a telescope to prove that the Earth moves around the Sun.

For teachers: a 17th-century Italian astronomer, physicist, and polymath who played a central role in the Scientific Revolution. His support for heliocentrism led to a famous conflict with the Catholic Church.

## Examples

- Galileo used his telescope to look at the moons of Jupiter.
- Many historians consider Galileo the father of modern observational astronomy because of his improvements to the telescope.
- The conflict between Galileo and the Roman Inquisition remains a defining historical example of the tension between empirical scientific observation and established religious authority.

## Usage notes

- Used as a proper noun to refer to the historical figure; occasionally used as a countable noun to refer to spacecraft or projects named after him.

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