halve
verb [ I or T ]
uk/hɑːv/ usto reduce a number or amount by 50 per cent, or to be reduced by 50 per cent:
Canada, Japan, and the EU are committed to halving global emissions by 2050.
Pre-tax profits nearly halved last year to £14m.
halve the amount/number/cost of sth The industry's rush of consolidation in the last decade nearly halved the number of banks in the U.S. to around 7,500.