unphenomenal

Etymology tree
Proto-Indo-European *né
Proto-Indo-European *n̥-
Proto-Germanic *un-
Proto-West Germanic *un-
Old English un-
Middle English un-
English un-
Proto-Indo-European *bʰeh₂-der.
Proto-Hellenic *pʰáňňō
Ancient Greek φαίνω (phaínō)
Ancient Greek φαινόμενον (phainómenon)bor.
Late Latin phaenomenonder.
English phenomenon
Proto-Indo-European *h₂el-der.?
Proto-Italic *-ālis
Latin -ālisbor.
Old French -albor.
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Latin -ālis
Old French -elbor.
▲
Latin -ālisbor.
Middle English -al
English -al
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Ancient Greek φαινόμενον (phainómenon)bor.
French phénomène
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Old French -al
Middle French -al
French -al
French phénoménalbor.
English phenomenal
English unphenomenal
From un- + phenomenal.