What does eccentric mean?
"Eccentric" describes someone or something that departs from what is conventional or expected, especially in behavior, style, or opinion. Calling a person eccentric usually suggests harmless, even endearing originality — the artist who paints only at night, the professor who wears mismatched socks — rather than anything alarming. The word also has precise technical uses: in geometry and astronomy, "eccentric" means off-center or describing an orbit that deviates from a perfect circle, which is in fact the older sense. As a noun, an eccentric is a person of markedly unconventional habits. The term derives from Greek roots meaning "out of center," entered English in the sixteenth century via Latin and French, and its figurative sense developed from this astronomical idea of being displaced from a central point. Useful and versatile, it lets speakers acknowledge difference without harsh judgment, making it a favorite for affectionate characterization.
Unconventional, peculiar, or slightly strange in behavior, appearance, or opinions, typically in a way regarded as amusing or endearing.
"He was an eccentric old man who collected vintage typewriters."
Not placed or moving symmetrically about a center; deviating from a circular path (used in geometry and astronomy).
"The planet's eccentric orbit takes it far from the star at certain points."
This is the older, technical sense, common in astronomy, engineering, and mechanics.
A person who behaves in an unconventional, idiosyncratic way.
"The village was full of lovable eccentrics."
The plural applies to the noun sense referring to people of unconventional habits.
"The town's eccentrics were celebrated rather than shunned."
In medieval astronomy, 'eccentric' described a planet orbiting off-center — the word literally means 'out of the middle.'
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of eccentric
Eccentric comes from Medieval Latin "eccentricus," from Greek "ekkentros" (ek-, 'out of' + kentron, 'center'), originally an astronomical term for orbits not centered on Earth. It entered English in the sixteenth century in this technical sense, and by the seventeenth century had acquired its figurative sense of deviating from conventional norms. It shares the Greek root "kentron" (sharp point, center) with words such as geocentric, heliocentric, egocentric, and centrifugal.
Related word forms
How eccentric is actually used
The adjective usually carries a mild, often affectionate connotation — suggesting harmless individuality rather than mental illness or menace. It is common in both formal and informal registers, and frequently used of artists, academics, aristocrats, and inventors.
Easily confused with eccentric
'Eclectic' means selecting ideas from a wide range of sources, while 'eccentric' means unconventional or odd.