\listfiles
\documentclass{article}
\usepackage{glossaries}

\newglossaryentry{foo}{%
  name=foo,
  plural=foox,
  description=bar
}

\begin{document}
\section{\glsentryname{foo}}
\section{\glsentrytext{foo}}
\section{\glsentryplural{foo}}
\section{\Glsentryname{foo}}
% \section{\Glsentrytext{foo}}
% \section{\Glsentryplural{foo}}
\end{document}
