subdimidius

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.

sub -dīmĭdĭus, a, um, adj., of a number,

half as much less , less by one half of itself (i. e. that bears to another the ratio of 2 to 3): numerus (opp. superdimidius), Mart. Cap. 7, § 761.