# What is an Eternal Word™?

This puzzle is based off the What is a Word™ and What is a Phrase™ series started by JLee and their spin-off What is a Number™ series.

If a word conforms to a certain rule, I call it an Eternal Word™. Use the following examples to find the rule:

$$% set Title text. (spaces around the text ARE important; do not remove.) % increase Pad value only if your entries are longer than the title bar. % \def\Pad{\P{0.0}} \def\Title{\textbf{ Eternal }} % \def\S#1#2{\Space{#1}{20px}{#2px}}\def\P#1{\V{#1em}}\def\V#1{\S{#1}{9}} \def\T{\Title\textbf{Words}^{\;\!™}\Pad}\def\NT{\Pad\textbf{Not}\T\ }\displaystyle \smash{\lower{29px}\bbox[yellow]{\phantom{\rlap{rubio.2019.05.15}\S{6px}{0} \begin{array}{cc}\Pad\T&\NT\\\end{array}}}}\atop\def\V#1{\S{#1}{5}} \begin{array}{|c|c|}\hline\Pad\T&\NT\\\hline % \text{ASKING}&\text{ANSWERING}\\ \hline \text{ATARI}&\text{KONAMI}\\ \hline \text{NINTENDO}&\text{SEGA}\\ \hline \text{ASTEROIDS}&\text{PACMAN}\\ \hline \text{RACHEL}&\text{MONICA}\\ \hline \text{CHANDLER}&\text{PHOEBE}\\ \hline \text{PINK}&\text{FUCHSIA}\\ \hline \text{MAGENTA}&\text{LAVENDER}\\ \hline \text{EARTH}&\text{PLUTO}\\ \hline \text{DWARF}&\text{MIDGET}\\ \hline \text{PLANET}&\text{PLANETOID}\\ \hline \text{70}&\text{69}\\ \hline \text{PROPER}&\text{IMPROPER}\\ \hline \text{FACTORY}&\text{FACTOR}\\ \hline \text{FLATTER}&\text{FATTER}\\ \hline \end{array}$$

The puzzle satisfies the series' inbuilt assumption, that each word can be tested for whether it is an Eternal Word™ without relying on the other words.

These are not the only examples, there are more of both Eternal Words™ and Not Eternal Words™.

CSV version:

ASKING,    ANSWERING
ATARI,     KONAMI
NINTENDO,  SEGA
ASTEROIDS, PACMAN
RACHEL,    MONICA
CHANDLER,  PHOEBE
PINK,      FUCHSIA
MAGENTA,   LAVENDER
EARTH,     PLUTO
DWARF,     MIDGET
PLANET,    PLANETOID
70,        69
PROPER,    IMPROPER
FACTORY,   FACTOR
FLATTER,   FATTER


An Eternal Word™ is

a word where you can remove the first and last letter to produce another word.

ATARI → TAR
NINTENDO → INTEND
ASTEROIDS → STEROID
RACHEL → ACHE
CHANDLER → HANDLE
PINK → IN
MAGENTA → AGENT
EARTH → ART
DWARF → WAR
PLANET → LANE
SEVENTY → EVENT
PROPER → ROPE
FACTORY → ACTOR
FLATTER → LATTE

The name:

"Eternal" means "without end", and you can make new words by removing both ends of an Eternal Word™.

• that was fast. +1 Commented Jul 24, 2019 at 9:20
• (+1): wow, well done! :P Commented Jul 24, 2019 at 9:51
• How is 70 eternal then? Commented Jul 24, 2019 at 23:55
• @Eugene Perhaps rot13(Friragl → rirag)? Commented Jul 25, 2019 at 6:05
• @Eugene I suspect it's meant to be spelled out as SEVENTY Commented Jul 25, 2019 at 8:42