演变路径（由近及远）
词源说明
From Middle English -ik, from Old French -ique, from Latin -icus, from Proto-Indo-European *-kos, *-ḱos, formed with the i-stem suffix *-i- and the adjectival suffix *-kos, *-ḱos. Compare Ancient Greek -ικός (-ikós), Sanskrit -इक (-ika) and Old Church Slavonic -ъкъ (-ŭkŭ). Doublet of -y; compare also -ac.
Proto-Indo-European *-kos on noun stems carried the meaning 'characteristic of, like, typical, pertaining to', and on adjectival stems it acted emphatically.
释义（英文）
后缀 Suffix
- Used to form adjectives from nouns with the meaning “of or pertaining to”.
- (chemistry) Used to denote certain chemical compounds in which a specified chemical element has a greater oxidation number than in the equivalent compound whose name ends in the suffix -ous. For example sulphuric acid (H₂SO₄) has more oxygen atoms per molecule than sulphurous acid