Nature notebook

Find three groups of three connected words.

Mistakes left: ●●●●

Choose three words, then submit your group.

Puzzle notes

This original practice board has nine words and three intended categories. Look for specific shared meanings rather than a broad association. It is part of TrioNine’s 38-puzzle collection, published October 1, 2026.

Words on this board: PETAL, STAMEN, SEPAL, KNEE, ELBOW, ANKLE, BAROMETER, ANEMOMETER, RAIN GAUGE.

Reveal this puzzle’s three groups and explanations

Parts of a flower

PETAL · STAMEN · SEPAL

These are structures found in a flower.

Body joints

KNEE · ELBOW · ANKLE

These connect bones and allow movement.

Weather instruments

BAROMETER · ANEMOMETER · RAIN GAUGE

These measure air pressure, wind speed and precipitation respectively.

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