All 3 Uses of

recede
in
The House of Hades

The Mist receded to the edges of the courtyard.†
p. 17.7 *

receded = move away or diminished (became less)

On the port-side wall, the huge ugly face receded so that Leo could see the entire creature—another gnome chimp, in even crazier clothes.†
p. 74.5

He willed the poison to recede, creating a small path of retreat along the edge of the cliff.†
p. 363.9

recede = to move away or diminish (become less)

Definition:

to move away or diminish (become less)

The exact meaning of recede depends upon its context. For example:

"We can't move back in until the floodwaters recede." -- diminish and move away
"Her fear receded." -- diminished
"The waves first advance and then recede." -- move away
"The news story receded into the background as it was replaced by new stories." -- received diminished attention
"a receding hairline" -- diminished hair (each year the line where hair stops growing is higher on the forehead)
"She has a receding chin." -- sloping back (as contrasted to sticking out)