hemerology

The story

1. Proto-Indo-European · derived from*-i-eh₂
2. Proto-Indo-European · derived from*leǵ-“to gather”
3. Ancient Greek · derived from-λογῐ́ᾱ
4. Proto-Indo-European · derived from*h₂eh₃-“be hot, burn”
5. Ancient Greek · derived fromἡμέρᾱ“day; date”
6. English todayhemerology

From Ancient Greek ἡμέρᾱ (hēmérā, “day; date”) (a variant of ἦμαρ (êmar, “day”), ultimately from Proto-Indo-European *h₂eh₃- (“be hot, burn”)) + -ology (from Ancient Greek -λογῐ́ᾱ (-logĭ́ā, suffix indicating the study of something, or a branch of knowledge), from λόγος (lógos, “word; explanation; subject matter”) (from λέγω (légō, “to arrange, put in order”), from Proto-Indo-European *leǵ- (“to gather”)) + -ίᾱ (-íā, suffix forming a feminine abstract noun) (ultimately from Proto-Indo-European *-i-eh₂ (suffix forming a collective noun))).

Words from the same roots