%%
%% The LaTeX Companion, 3ed
%%
%% Example 4-1-5 on page I-257 in "Customizing the \protect \nxLenv  {description} list environment".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{147.0pt}
%StartShownPreambleCommands
 \renewcommand\descriptionlabel[1]%
   {\hspace{\labelsep}\textsf{\bfseries #1}}
%StopShownPreambleCommands

\begin{document}
 \begin{description}
 \item[An item] Its description with enough text
        to fill more than one line in the example.
 \item[Another item]  Now just two lines of text.
 \end{description}
\end{document}