I personally don't count Coleus (nor Alternanthera nor Acalypha nor Crotons). These - in my opinion - are plants that have naturally colored foliage. A variegated plant - again in my opinion - is a plant that normally has plain foliage but occurs in a 'striped' or colored form as well. Like for instance this variegated Ponytail Palm (Beaucarnea recurvata)
