Moving right along:

AERIOUS

PRONUNCIATION: (AY-ree-uhs)

MEANING: adjective: Of or like air; airy.

ETYMOLOGY: From Latin aereus/aerius, adjectival form of aer (air). Earliest documented use: 1594.

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Ooh, lots of options here. And interestingly most of the changes could go equally well in front of the A or between the A and the E, with opposite definitions.

AERIOUS - nesting in high places (the "Identity Transform")

AFERIOUS - without iron; anemic

TERIOUS - weepy
XERIOUS - dry