sol ‧ i ‧ dar ‧ i ‧ ty /ˌsɒləˈdærəti, ˌsɒlɪˈdærəti $ ˌsɑː-/ BrE AmE noun [uncountable]
[ Word Family: noun : ↑ solid , ↑ solidarity , ↑ solidity , solids, ↑ solidification ; verb : ↑ solidify ; adverb : ↑ solidly ; adjective : ↑ solid ]
loyalty and general agreement between all the people in a group, or between different groups, because they all have a shared aim:
a gesture of solidarity
an appeal for worker solidarity
show/express/demonstrate your solidarity (with somebody)
I come before you today to express my solidarity with the people of New York.