I. par ‧ ti ‧ san 1 /ˌpɑːtəˈzæn, ˌpɑːtɪˈzæn $ ˈpɑːrtəz ə n, -s ə n/ BrE AmE adjective
1 . strongly supporting a particular political party, plan, or leader, usually without considering the other choices carefully:
British newspapers are highly partisan.
2 . relating to the fighting of an armed group against an enemy that has taken control of its country:
the nature of partisan warfare
II. partisan 2 BrE AmE noun [countable]
[ Date: 1500-1600 ; Language: French ; Origin: Old Italian partigiano , from parte 'party, part' , from Latin pars ; ⇨ ↑ part 1 ]
1 . someone who strongly supports a political party, plan, or leader:
a media campaign to represent Democrats as angry partisans
2 . a member of an armed group that fights against an enemy that has taken control of its country
—partisanship noun [uncountable]