h₂ster-

Reflected in Latin stella (from *stēr-lā), Greek astḗr (whence asteroid, astronomy, disaster), and E‍​‍​‌​‌​‍​‌​‍​‍​‌​‍​‌​‌​‌​‌​‍​‌​‍​‌​‍​‍​‌​‍​‍​‍​‌​‍​‍​‌​‍​‌​‌​‌nglish star from Proto-Germanic *sternō.

Discussion

The word for star, *h₂stér- (plural *h₂stéres), is attested across the major branches with regular phonological development and consistent semantics.‍​‍​‌​‌​‍​‌​‍​‍​‌​‍​‌​‌​‌​‌​‍​‌​‍​‌​‍​‍​‌​‍​‍​‍​‌​‍​‍​‌​‍​‌​‌​‌ The initial cluster *h₂st- produces different outcomes in different branches, making it a useful diagnostic.

Latin stella (from *stēr-lā, a diminutive formation with l-suffix) yields stellar, constellation, and the name Stella. The direct continuation *stēr-lā rather than the simple *h₂stér- is a specifically Latin innovation.

Greek astḗr (ἀστήρ, "star") preserves the root more directly, with a prothetic vowel a- (from *h₂). The enormous derivative vocabulary includes asteroid ("star-like"), astronomy ("star-law"), astrology ("star-discourse"), astronaut ("star-sailor"), aster (the flower, for its star shape), asterisk ("little star"), and disaster (disastro, through Italian, "ill-starred").

Sanskrit stṛ́- (from *h₂stér- with loss of the laryngeal) is less common in attested texts, where tā́rā ("star," from a related formation) is preferred. The Avestan star- confirms the Indo-Iranian reconstruction.

English star (from Old English steorra, Proto-Germanic *sternō) shows the regular Germanic development. German Stern, Dutch ster, and Old Norse stjarna continue the same form. The initial cluster *st- is preserved in Germanic (the laryngeal *h₂ having been lost without trace in this position).

Old Irish ser ("star") and Welsh seren continue the Celtic reflex. Armenian astł and Tocharian B ścire extend the attestation to those branches.

The cultural importance of stars in PIE society is suggested not only by the existence of a common word but by the derivative *h₂stér-lo- (> Latin stella, English stellar), which implies a diminutive or affectionate formation — the stars as "little bright ones."

Laryngeal Analysis

Initial h₂ (a-colouring).

Ablaut

r-stem noun.