ethnic group

main, principal

centrality

area, district, particular geographic region

he / distal demonstrative, something far off removed from both speaker and listener: that / boyfriend

distal demonstrative, something far off removed from both speaker and listener: that, yon / particularly, male personal third person pronoun: he / by extension from he: boyfriend

he; boyfriend

to research, to study

a piece of research, a study, investigation

(taxonomy) a tribe / (chemistry) a group (column in the periodic table)