23.1 Defining Abbrevs

C-x a g

Define an abbrev to expand into some text before point (add-global-abbrev).

C-x a l

Similar, but define an abbrev available only in the current major mode (add-mode-abbrev).

C-x a i g

Define a word in the buffer as an abbrev (inverse-add-global-abbrev).

C-x a i l

Define a word in the buffer as a mode-specific abbrev (inverse-add-mode-abbrev).

M-x kill-all-abbrevs

After this command, no abbrev definitions remain in effect.

The usual way to define an abbrev is to enter the text you want the abbrev to expand to, position point after it, and type C-x a g (add-global-abbrev). This reads the abbrev itself using the minibuffer, and then defines it as an abbrev for one or more words before point. Use a numeric argument to say how many words before point should be taken as the expansion. For example, to define the abbrev ‘foo’ as in the example above, insert the text ‘find outer otter’, then type
C-u 3 C-x a g f o o RET.

An argument of zero to C-x a g means to use the contents of the region as the expansion of the abbrev being defined.

The command C-x a l (add-mode-abbrev) is similar, but defines a mode-specific abbrev. Mode-specific abbrevs are active only in a particular major mode. C-x a l defines an abbrev for the major mode in effect at the time C-x a l is typed. The arguments work the same way they do for C-x a g.

If the text of an abbrev you want is already in the buffer instead of the expansion, use command C-x a i g (inverse-add-global-abbrev) instead of C-x a g, or use C-x a i l (inverse-add-mode-abbrev) instead of C-x a l. These commands are called “inverse” because they invert the meaning of the argument found in the buffer and the argument read using the minibuffer.

To change the definition of an abbrev, just add the new definition. You will be asked to confirm if the abbrev has a prior definition. To remove an abbrev definition, give a negative argument to C-x a g or C-x a l. You must choose the command to specify whether to kill a global definition or a mode-specific definition for the current mode, since those two definitions are independent for one abbrev.

M-x kill-all-abbrevs removes all existing abbrev definitions.