# How to bold just one word in a line

If I have a line of text, how do I make just the first word bold?

I tried this:

\bf{NTn} = Number of lines


but it made the entire line bold.

-
Use \textbf{Some text in bold}. –  Ali Mehrizi May 16 '12 at 5:16
–  Werner May 16 '12 at 5:35
\bf is an outdated font switch, not a macro with an argument, i.e. itr works to the end of the group. You would need to use {\bf NTn} instead, but should not use the font commands any longer. Use \textbf{..} or {\bfseries ..} instead. –  Martin Scharrer May 16 '12 at 7:45

You should not use \bf. Instead use {\bfseries ....}.

\documentclass{article}
\usepackage{amsmath}
\begin{document}

{\bfseries NTn} = Number of lines

$\boldmath{NTn} + \mathbf{NTn} + \boldsymbol{\pi} + \pmb{\pi}$ = Number of lines.

\verb|\boldsymbol| and \verb|\pmb| are provided by \verb|amsmath| package. Note that \verb|\mathbf| has no effect on symbols like $+$ or $-$ or $\pi$ etc.

\end{document}


-
Thanks, but what if I need to bold the following: $NT_n$ ? {\bfseries $NT_n$} doesn't work..... –  ngramsky May 16 '12 at 5:16
@ngramsky, for math mode, use \mathbf{e^{j\pi}=-1}'. –  Ali Mehrizi May 16 '12 at 5:22
For bolding math you can use \boldmath, \boldsymbol or \pmb. For mor details see here –  adn May 16 '12 at 5:23
@ngramsky: see the edited answer. –  Harish Kumar May 16 '12 at 5:29
For regular, bold and italics math, use the bm package:
\documentclass{article}
$NTn=\bm{NTn}=\mbox{Number of lines}$
`