(~s)
1.
A ~ is a race in which people run a distance of 26 miles, which is about 42 km.
...running in his first ~...
Rodgers can also claim four victories in the New York Marathon.
N-COUNT
2.
If you use ~ to describe an event or task, you are emphasizing that it takes a long time and is very tiring.
People make ~ journeys to buy glass here.
...a ~ session of talks with government representatives.
ADJ: ADJ n emphasis