1. verb /wɔːl/
a) To boil.

He walled the study with books.

b) To well, as water; spring.

They had walled in the garden

2. noun /wɔːl/
a) A spring of water.

The town wall was surrounded by a moat.

b) A rampart of earth, stones etc. built up for defensive purposes.

Were adding another wall in this room during the remodeling.

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