Morph

"Watch," said Morph, and it took a single root — the idea of to act. "Right now I'm a doing-word: act." It gave a little bow. Then it flicked on a new ending and its whole shape shifted. "Now I'm a person-who-does-it: actor." Another flick. "Now I'm a describing-word: active." Another. "Now I'm the whole event: action."

Four creatures — and every one of them was Morph, wearing the same root under a different ending.

The young creatures gasped. They'd thought act, actor, active, action were four separate words to memorize. They were one root in four costumes.

"That's the whole trick," said Morph. "The root is who I am. The ending is the job I'm doing right now. Add one kind of ending and a root becomes a thing. Add another and it becomes a describer. Add another and it becomes a doing-word." It spun. "Same heart. Different coat. Different job."

This changed how the creatures read every word. When they met an unfamiliar word ending, they stopped panicking and asked Morph's question instead: what job is this ending making the root do? An ending that meant "one who does it." An ending that meant "the state of being it." An ending that turned an action into a describer. The endings were like little job-badges pinned to the root.

Morph made one honest mistake worth keeping. It once changed an ending and insisted the meaning had completely changed too. The lexicographer gently corrected it: "The core meaning stays — that's the root. You changed the job, not the heart. Happy and happiness and happily all still mean the same warm thing; you just made it a describer, then a thing, then a how." Morph nodded. Change the job, keep the heart.