On a user-by-user basis, you can enable or disable shorthand flexfield entry for yourself (for all key flexfields that use it) by setting your user profile option Flexfield: Shorthand Entry to an appropriate value. Your System Administrator can set this profile option at other levels (such as for a responsibility).
However, in some forms, such as forms where you define new key flexfield combinations (combinations forms), you do not see the shorthand window even if shorthand entry is enabled. For example, you cannot use shorthand entry in the Oracle General Ledger Define Accounting Flexfield Combinations form. See: Disabling or Enabling a Shorthand Alias.
Shorthand Aliases Window