A variant of 'flower' — flour was the 'flower' (finest part) of ground grain, only distinguished in spelling around 1830.
A powder made by grinding grain, used to make bread, cakes, and pastry.
A variant spelling of 'flower' — flour was originally 'the flower (finest part) of the meal.' Both words derive from Old French flur 'flower, blossom,' from Latin flōrem 'flower.' The spellings flour and flower were interchangeable until the 19th century