What is a Tight Word™?

Question

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

Answer 1

A Tight Word™

contains only letters without ascenders or descenders in lowercase. That is, it contains a c e i m n o r s u v w x z, but doesn't contain b d f h k l t, which extend above the midline, or g j p q y, which extend below the baseline.