clears values and definitions for the symboli.


clears values and definitions for all symbols whose names match any of the string patterns formi.


  • Clear does not clear attributes, messages, or defaults associated with symbols.
  • Clear allows abbreviated string patterns containing the following metacharacters:
  • *zero or more characters
    @one or more characters, excluding uppercase letters
    \\*, etc.literal *, etc.
  • Clear["context`*"] clears all symbols in a particular context.
  • Clear is HoldAll.
  • Clear does not affect symbols with the attribute Protected.


open allclose all

Basic Examples  (2)

Clear a variable:

Clear a function definition:

Scope  (4)

Clear values of variables:

Clear functions (downvalues):

Clear upvalues:

Clear several symbols:

Generalizations & Extensions  (2)

Clear all symbols in a given context:

Specify symbols to clear as string patterns:

Applications  (1)

Clear any old definitions before making new ones:

Properties & Relations  (2)

Clear does not remove defaults, options, or attributes:

Use ClearAll to clear everything:

Use =. to clear definitions with a particular left-hand side:

Clear all definitions:

Possible Issues  (1)

Protected symbols cannot be cleared:

Use Unprotect to clear definitions of protected symbols:

Neat Examples  (1)

Clear the definitions of all symbols in the current context:

Wolfram Research (1988), Clear, Wolfram Language function,


Wolfram Research (1988), Clear, Wolfram Language function,


@misc{reference.wolfram_2020_clear, author="Wolfram Research", title="{Clear}", year="1988", howpublished="\url{}", note=[Accessed: 19-January-2021 ]}


@online{reference.wolfram_2020_clear, organization={Wolfram Research}, title={Clear}, year={1988}, url={}, note=[Accessed: 19-January-2021 ]}


Wolfram Language. 1988. "Clear." Wolfram Language & System Documentation Center. Wolfram Research.


Wolfram Language. (1988). Clear. Wolfram Language & System Documentation Center. Retrieved from