threefold

adj

1. (not-comparable)Three times as great.

   “"We recognise that electrifying more of the railway is likely to be necessary to deliver decarbonisation," it stated. There's clearly a growing momentum in that direction, but some significant hurdles have still to be overcome - not least the legacy of the three-fold increase in cost on the Great Western Electrification Programme, which has become the poster project for expensive wiring.”

2. (not-comparable)Triple.

adv

1. (not-comparable)By a factor of three.

noun

1. An algebraic variety of dimension 3.

   “In this way, we find some new pairs (h#123;1,1#125;,#92;#59;h#123;2,1#125;) of Hodge numbers of Calabi-Yau threefolds.”

verb

1. (transitive)To make threefold; to triple.