Calcaneal' refers to the heel bone (properly called the 'calcaneus' or 'calcaneum'. 'Oedema' just means 'swelling'.
Calcaneal oedema very commonly occurs with plantar fasciiitis but is really more similar to calcaneal apophysitis - but the adult version! Let me reassure you, if you have finished growing, you will not be able to get calcaneal apophysitis.
Calcaneal oedema is simply bruising and can be really quite brutal to put up with. Unlike plantar fasciitis, it gets worse as time goes on during the day, and will feel like you are walking on a stone.
If you find that you get pain when you first get up and then have pain at the end of the day or if you have been walking around barefoot for a while, then it is quite likely you have calcaneal oedema. Likewise, if you are feeling pain in your foot when you are lying in bed or sitting on the sofa after a busy day, this is a more likely diagnosis.
Very rarely (I've not seen one yet, neither have my mentors who have hundreds of years of experience between them!), symptoms when you are off your feet can be associated with more sinister problems. This said, it is far more likely to be a back problem presenting in your feet.
Experienced podiatrists who diagnose and treat heel pain regularly will be able to clinically diagnose (hear your history, ask relevant questions and physically assess you) and differentiate between bruising, fractures, back problems causing heel pain and the big, bad stuff. Likewise, experienced podiatrists should be qualified to organise imaging to confirm your symptoms.
Bone bruising, the little annoying cousin of a stress fracture (but nowhere near as bad!).
It might feel like you are walking on a stone, but once we get ahead of that, you should find your symptoms vastly improved.