single
adjective [ before noun ]
uk/ˈsɪŋɡl/ usone only:
Journalism often relies on a single source.
Is a thread of e-mails a single document or many?
a single use card
TRANSPORT UK
travelling or allowing travel in only one direction:
a single fare/ticket/journey
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single
noun [ C ]
uk/ˈsɪŋɡl/ us TRANSPORT UK
a ticket for a journey to a place, but not back again:
single to somewhere A single to London, please.
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MONEY US
a piece of paper money worth one dollar