Ancient Greek 
Etymology 1 
Uncertain. Perhaps from a Proto-Indo-European *h₂endʰos, with cognates including Sanskrit अन्धस (ándhas, “grass, cabbage”), Albanian ënde, Old Armenian անդ (and, “field”), and possibly Old Frisian åndul.
ἄνθος (genitive ἄνθεος or ἄνθους) n, third declension; (anthos)
- flower, blossom, bloom
- froth, scum
- bloom, peak
- brightness, brilliance
This inflection pattern originally had a sigma (i.e. ἄνθεσος), which was dropped early on in the history of Ancient Greek.
The irregular accentuation of this paradigm is explained by the fact that it is the contracted version of the above paradigm. Usually the genitive plural in Attic writers is ἀνθέων (antheōn)
ἄνθος (genitive ἄνθου) m, second declension; (anthos)
- a small bird, possibly the yellow wagtail.