market leader
noun[C]
COMMERCEukusthecompanythatsellsmost of aproductorservicein aparticularmarket:
market leader for/in sthThesupermarketchainis now themarketleaderinbabygoods.
Hisaimis tobecomethemarketleaderinprovidingdesktopsolutionstodoctorsand thewiderhealthcarecommunity.
the global/world market leaderThegroupis theworldmarketleaderincarelectronics.
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market challenger
market follower
market nicher