aerostatically

Etymology tree
Proto-Indo-European *h₂ews-
Proto-Indo-European *h₂ewsér
Proto-Hellenic *auhḗr
Ancient Greek ᾱ̓ήρ (āḗr)
Ancient Greek ἀέρος (aéros)der.
English aero-
Ancient Greek στᾰτῐκός (stătĭkós)der.
Latin staticusder.
English static
English aerostatic
Proto-Italic *-ālis
Latin -ālisbor.
Old French -albor.
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Latin -ālis
Old French -elbor.
▲
Latin -ālisbor.
Middle English -al
Middle English -ly
Middle English -ally
English -ally
English aerostatically
From aerostatic + -ally.