I am listing some nomenclature with the following part of code:

```
\documentclass[12pt]{article}

\newlength{\nomenlabelindent}
\setlength{\nomenlabelindent}{4em}
\newenvironment{nomenclature}{%
\newcommand\entry[2]{%
   \hangindent\nomenlabelindent\noindent\makebox[\nomenlabelindent][l]{##1\quad}\ignorespaces##2\par}%
   \section*{NOMENCLATURE}}{\par\addvspace{12pt}}

\begin{document}

\begin{nomenclature}
    \entry{$\rho$}  {Density} 
    \entry{$T$}  {Temperature} 
    \entry{$v$}{Volume}
    \entry{$t$}{time}
    \entry{$\Gamma$}{Number flux density}
    \entry{$\sigma$}{Sp. Charge density}
\end{nomenclature}

\end{document}

```

The Output is as:

[![enter image description here](https://i.stack.imgur.com/0Sch5.jpg)](https://i.stack.imgur.com/0Sch5.jpg)

**Question**: I want to add one more column on the right side to show the respective units of each entry. This should also have a defined indentation. For reference:

[![enter image description here](https://i.stack.imgur.com/cvqdh.jpg)](https://i.stack.imgur.com/cvqdh.jpg)

Thanks in advance and any help would be greatly appreciated.