the willingness shown by, an act of, working or acting together for a common purpose

mutual effort

the firing of guns from two or more points so that the lines of fire cross

switch, exchange

a place where roads join a motorway etc; (an instance of) the exchange of ideas, methods etc

switch, exchange

needing, depending on, each other

shared, common

the effect of two things on each other

interaction

(of love, friendship, respect, feelings, opinions etc) shared; each to the other(s); common to two or more people

shared, common

given and received in return

exchanged, alternate

switch, exchange

switch, exchange