If a word conforms to a special rule, I call it a Tight Word™.
Use the list of examples below to find out what this rule is.
$$\begin{array}{|c|c|} \hline \textbf{Tight Words™}&\textbf{Not Tight Words™}\\ \hline \text{NUMEROUS}&\text{MANY}\\ \hline \text{CONCUR}&\text{AGREE}\\ \hline \text{NERVOUSNESS}&\text{JUMPINESS}\\ \hline \text{VERONA}&\text{MANTUA}\\ \hline \text{WORN}&\text{PATCHED}\\ \hline \text{MAUVE}&\text{PURPLE}\\ \hline \text{RAXACORICO}&\text{FALLAPATORIUS}\\ \hline \text{MENACE}&\text{DENNIS}\\ \hline \text{ROME}&\text{ITALY}\\ \hline \text{NICENESS}&\text{KINDNESS}\\ \hline \text{VIEWS}&\text{PANORAMA}\\ \hline \text{CURVACEOUS}&\text{ROUNDED}\\ \hline \end{array} $$
Text-only version for analysis:
NUMEROUS MANY CONCUR AGREE NERVOUSNESS JUMPINESS VERONA MANTUA WORN PATCHED MAUVE PURPLE RAXACORICO FALLAPATORIUS MENACE DENNIS ROME ITALY NICENESS KINDNESS VIEWS PANORAMA CURVACEOUS ROUNDED