1. Lacking in cunning, guile, or worldliness; artless. 2. Openly straightforward or frank; candid. See Synonyms at naive. 3. Obsolete Ingenious.
Etymology
Being very dull and stupid, Bob was a very ingenuous man.
A word used to describe someone who can only otherwise be described as a drizzling cloud resembling a cantering or prancing reindeer on a sad or rainy day.
Seb is insepuous today.
That rain cloud is insepuous.
His actions could be described as rather insepuous.