1 to increase three times in size or amount, or to make something do this: --
2 being or relating to a boy's voice that sings the highest notes, or an instrument that plays the highest notes: --
4 an occasion when a football club wins three major competitions in a single season: --
He can employ, and would employ, 25 men instead of 16, which would mean that in three years he had trebled his labour force.
My majority trebled; in fact it more than trebled.
Youth unemployment has actually trebled and gone up disproportionately.
On the same basis, the number of amenity dwellings has trebled to more than 8,500.
In the iron and steel trades unemployment has trebled since they came into office, and in engineering it has nearly trebled.
I think it has probably trebled, but certainly it has more than doubled, because it has doubled since about 1914.
If that is to be achieved, the upper value limit of £500 should be at least doubled, and perhaps even trebled.
The number of individual shareholders has more than trebled since 1979.