Definition
Definition[symbol]
prints as the definitions given for a symbol.
Definition["symbol"]
prints as the definitions given for the symbol named "symbol" if it exists.
Details

- Definition has attribute HoldAll.
- Definition[symbol] prints as all values and attributes defined for symbol.
- Definition does not show rules associated with symbols that have attribute ReadProtected.
Examples
open allclose allScope (3)
For built-in symbols, Definition gives attributes, defaults, and options:
For user-defined symbols, Definition gives attributes, defaults, options, and definitions:
Print the definitions of a symbol if it exists:

Properties & Relations (4)
For read-protected symbols, definitions are not given:
The information given by Definition is comprised of defaults, options, attributes, and values:
Information prints the values rendered by Definition, as well as usage messages:
?? is the same as Information:
Definition is HoldAll:
Possible Issues (1)
Definition is an output form; it does not evaluate:
Text
Wolfram Research (1988), Definition, Wolfram Language function, https://reference.wolfram.com/language/ref/Definition.html (updated 1996).
CMS
Wolfram Language. 1988. "Definition." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 1996. https://reference.wolfram.com/language/ref/Definition.html.
APA
Wolfram Language. (1988). Definition. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/Definition.html