Answer: Rhododendrons and azaleas are closely related. Modern references include azaleas under the same genus, Rhododendron. Some generalized distinctions exist but they are not totally consistent, for instance most azaleas are deciduous while most rhododendrons are evergreen.
The genus Rhododendron is part of the family Ericaceae. This family is commonly called the heath family and also includes Kalmia (mountain laurel), Vaccinium (blueberry) and about 200 others. I hope this helps.
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