'abnormal-flowered' originates from Modern English as a compound of the adjective 'abnormal' and the past-participial adjective-forming 'flowered'; 'abnormal' ultimately comes from Late Latin 'abnormālis' ('ab-' meaning 'away from' + 'normālis' meaning 'regular'), and 'flowered' derives from English 'flower' (from Old French/Latin 'flor-/flos, floris').

'abnormal' passed into Middle English from Late Latin/French forms (Middle English 'abnormal' or 'abnormaile'), while 'flower' developed from Old French 'flor' (itself from Latin 'flos, floris'); the compound 'abnormal-flowered' is a modern descriptive formation combining these elements to describe floral abnormality.

Initially the components meant 'away from the norm' and 'having flowers'; combined, the term has kept the straightforward meaning of 'having flowers that deviate from the normal form', used especially in botanical contexts.