cepheid
Upper-Intermediate (B2)
IPA: /ˈsɛfɪəd/
KK: /ˈsɛfɪd/
adjective
Definition
Connected to a type of star that varies in brightness over a regular period.
Example
Astronomers study cepheid stars to measure distances in the universe.
Conversation
Did you know that some stars are classified as cepheid variables?
Really? What makes them so special?
They change brightness in a regular pattern, which helps astronomers measure distances in space.
That's fascinating! I love how much we can learn from these cepheid stars.
Synonyms & Antonyms
Synonyms
variable
pulsating
stellar
Antonyms
static
fixed
unchanging
noun
Definition
A type of star that changes brightness in a regular pattern, which helps astronomers measure distances in space.
Example
Astronomers use cepheids to determine how far away galaxies are from Earth.
Conversation
Have you ever heard of a cepheid star?
Yeah, I read that they change brightness regularly.
Exactly! They help astronomers figure out distances in space.
Root Explanation
Cepheid is derived from the Greek word "kephaios" (meaning head), which refers to the star Delta Cephei, the prototype of a class of variable stars that pulsate in brightness. The term "Cepheid" thus describes a type of star characterized by its periodic changes in luminosity.
Memory Tip
Think of the Greek word for head ('kephaios') to remember that a Cepheid is a type of star that changes brightness periodically, like a head that can be seen from different angles.
Visually Confused Words
No commonly confused words.