I have the following:
\newcommand{\makeWord}[1]{%
\newcommand{\#1}{\textrm{#1}}}
\makeWord{AdditiveGroup}
\newcommand{\AdditiveGroup}{\textrm{AdditiveGroup}}
Unfortunately, I did not properly define the makeWord macro. How do I fix this?
\newcommand{\makeWord}[1]{%
\newcommand{\#1}{\textrm{#1}}}
\#1 is the two tokens \# (which would typeset a #) and 1 so is a syntax error as the first argument of \newcommand.
Try
\newcommand{\makeWord}[1]{%
\expandafter\newcommand\csname#1\endcsname{\textrm{#1}}}
Note this will make a mathord token if used in math. If you want to make an operator like \log it needs to be
\newcommand{\makeWord}[1]{%
\expandafter\newcommand\csname#1\endcsname{\mathop{\mathrm{#1}}}}
or use the amsopn \DeclareMathOperator command.