Social groups (6)
'social groups' is the definition.
(tribe is a kind of social group)
This is the entire clue.
(Other definitions for tribes that I've seen before include "Racial groups living in communities headed by chiefs" , "Clans" , "Groups of people related by blood" , "Groups of families in traditional societies" , "Social groups in traditional societies" .)
'social groups' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for castes that I've seen before include "Hindu social divisions or classes" , "Hereditary social classes among Hindus" , "Social divisions in India" .)
'social groups' is the definition.
(circle is a kind of social group)
This is the entire clue.
(Other definitions for circles that I've seen before include "Figures" , "Rings" , "Cliques in which people move" , "Surrounds" .)