Full of humanity? (8)
I believe the answer is:
thronged
'full' is the definition.
The answer and definition are not the same part of speech. However, past participle verbs and adjectives can occasionally define each other.
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for thronged that I've seen before include "Gathered together in crowd" , "Crowded like very busy street" , "Swarmed" , "Packed, crowded" , "Gathered in numbers" .)