asteroid

The word 'asteroid' is a modern scientific coinage from the early 19th century, directly constructed from classical Greek elements. Its first component, 'aster-', originates from the Greek noun 'astēr', meaning 'star', which itself descends from the Proto-Indo-European root 'h₂stḗr', also meaning star. The second component, '-oid', derives from the Greek adjectival suffix '-oeidēs', meaning 'having the form of, resembling', from 'eîdos' (form, shape). The term was coined by astronomer William Herschel to describe these newly discovered celestial bodies, which in telescopes appeared as star-like points of light rather than disks like planets. Thus, the literal meaning "star-like" perfectly captures their initial observed characteristic, even though their true nature as rocky, planet-like bodies was later understood.

Structure: aster (star) + oid (resembling) aster: From Greek 'astēr' (star). Functions as the core root denoting a star. oid: From Greek '-oeidēs' (having the form of, resembling). Functions as a suffix indicating likeness or resemblance.