going in at one side or end of something and out at the other side or end
The train passed through the tunnel in just a few seconds.
Sunlight streamed through the window, warming the room.
✦ Old English ‘þurh’, from Proto-Germanic *thurkh.
during the whole of a period of time from beginning to end
He studied through the night for his exam.
The shop stays open through the weekend.
from beginning to end without stopping; completely
She read the book straight through in one afternoon.
We walked through to the other side of town.
finished with something and no longer involved with it
Are you through with the scissors?
I'm through with that project.
by means of someone or something; using
I heard about the job through a friend.
She raised money through online donations.
up to and including a particular point in a series or period
The store is open Monday through Friday.
Tickets are valid ages 5 through 12.
(only before a noun) going the whole way without stopping or changing
We took a through train to London.
There's a through bus service to the airport.
in every part of a place or thing
Colorful lanterns were hung throughout the courtyard for the festival.
The smell of fresh paint lingered throughout the house.
during the whole of a period of time
She worked remotely throughout the summer.
It rained throughout the night.
everywhere; in every part
Laughter could be heard throughout.
Dust lay thick throughout.
for the entire duration; all the time
She remained optimistic throughout.
The baby slept soundly throughout.
a sudden important discovery, invention, or development that removes a barrier and allows significant progress
The scientist's unexpected breakthrough led to a life-saving drug.
A recent breakthrough in solar panel design has made renewable energy cheaper than ever.
