Anything that serves to support something; a prop.
A brick or stone structure built against another structure to support it.
Anything that supports or strengthens.
A buttress-root.
A feature jutting prominently out from a mountain or rock.
To support something or someone by supplying evidence.
To support something physically with, or as if with, a prop or buttress.
Something that facilitates
A person who helps a group to have an effective dialog without taking any side of the argument, especially in order to reach a consensus.