noun
theta
THEE-tuh
noun
1
A letter of the Greek alphabet (Θ, θ), also used in mathematics and science to represent an angle or variable.
"In the equation, theta represents the angle of rotation."
2
In finance, a measure of how quickly an option's value decreases as it approaches its expiration date.
"Traders watch theta closely as an option nears expiry."
How to Use Theta
Learner’s notesIn plain EnglishA Greek letter often used as a symbol for an angle in maths and physics, or "time decay" in finance.
Common pairings
theta angle
theta decay
Word Forms
thetas plural, Thetas plural
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In the equation, _____ represents the angle of rotation.
Etymology
From Greek theta, the eighth letter of the modern Greek alphabet.