1. departing from the right, normal, or usual course.
2. deviating from the ordinary, usual, or normal type; exceptional; abnormal; unusual; strange; bizarre; anomalous.
3. an aberrant person, thing, group, etc.
[word requested by fenouilaberrant]
“Twisted Wisp Eaters” by Mark Facey reminds me of some of Brian Froud’s creations.