Words & WritingGreek → English
Theta
/ˈθeɪtə/noun
The eighth letter of the Greek alphabet, standard notation for an angle in mathematics and for temperature in physics.
The Greek roots
θῆτα
thêta
eighth Greek letter
Literally: “wheel, from Phoenician ṭēth”
Follow a root:θῆτα1 word
The story of the word
Eighth letter, from Phoenician ṭēth. Athenian jurors used theta to vote for a death sentence, since it opens θάνατος, death, and Roman clerks put a theta beside the names of the dead on muster rolls, which is why old sources call it the sign of mortality. It also survived where Greek sounds did not: English th exists in Greek loanwords because θ was once an aspirated t, not the sound it makes now.
- How it travelled
- Phoenician → Ancient Greek → Latin → English
In a sentence
Solve for theta and check whether the answer is in radians.
Theta waves show up in the recording just before he drops off.