aster-, -aster, -astrous

(Greek: star, stars)

The sun, moon, and the stars would have disappeared long ago, had they happened to be within reach of predatory human hands.

—Havelock Ellis
A class comprising the starfish.
Relating to a star-shaped object or objects.
A fossil plant from the coal formations of Europe and America, now regarded as the branchlets (small, usually terminal branches) and foliage of calamites (a genus of extinct arborescent, tree-like, horsetails to which the modern horsetails (genus Equisetum) are closely related which were components of the under-stories of coal swamps of the Carboniferous, coal-bearing, period).
A type of vertebra with radiating, star-like calcifications extending to the chordacentrum and autocentrum.
A subphylum of echinoderms comprising the starfishes (Asteroidea) and brittle stars (Ophiuroidea) which includes one extinct and three living classes.

Links to star words Other "star" units: astro-, sidero-, stell-.