In LaTeX, how does one get a colon instead of a full stop after a theorem?

I want to know if there is some way to change that full st开发者_如何学运维op after Definition. to a colon, i.e. to get Definition: (and for the other environments in the "definition" theoremstyle).

The easiest approach may be to define yourself a new style:

\newtheoremstyle{stylename} % name of the style to be used

{spaceabove}% measure of space to leave above the theorem. E.g.: 3pt

{spacebelow}% measure of space to leave below the theorem. E.g.: 3pt

{bodyfont}% name of font to use in the body of the theorem

{indent}% measure of space to indent

{headfont}% name of head font

{headpunctuation}% punctuation between head and body

{headspace}% space after theorem head; " " = normal interword space

{headspec}% Manually specify head

In this case, you would copy the existing definition style, and then change the value of headpunctuation.

AMS LaTeX should be included in any modern distribution. It (or the amsthm standalone package ([docs here PDF link!)) provides the \theoremstyle and \newtheoremstyle commands.