what is the symbol of theta
The lower-case letter Î¸ is used as a symbol for: 1  A plane angle in geometry. 2  A special function of several complex variables. 3  One of the Chebyshev functions in prime number theory. 4  The potential temperature in meteorology. 5  The score of a test taker in item response theory.he upper-case letter Î¸ is used as a symbol for: 1  Quantity or temperature, by SI standard (in italics). 2  Dimensionless temperature in transport phenomena. 3  An asymptotically tight bound in the analysis of algorithms (big O notation). 4  A certain ordinal number in set theory.