adj
online
ON-lyn
adj
1
Connected to the internet or another network, and actively available or in use.
"Her laptop has been online all day downloading updates."
"The store only sells its limited-edition sneakers online."
2
Of a factory, power plant, or piece of equipment: switched on and actively running.
"The new reactor is expected to come online next spring."
verb
1
To bring a system, service, or piece of equipment into active, running use.
"Engineers onlined the backup generator within minutes of the outage."
How to Use Online
Learner’s notesIn plain EnglishConnected to a network (usually the internet) and currently active, or being switched into active use.
Common pairings
shop online
come online
online store
stay online
Word Forms
more online comparative, onlined past tense, onlines singular, most online superlative
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Her laptop has been _____ all day downloading updates.
Etymology
From on + line, first used around the 1950s for equipment directly connected to and controlled by a computer.