Definition of neanderthalensis

(Kenneth Allsop, The Bootleggers and Their Era...)

He was also at_the_same_time gaining practical experience as a safe_breaker and highwayman , and learning how to shoot to kill from a Neanderthal convicted murderer named Gene_Geary , later committed to Chester_Asylum as a homicidal maniac , but whose eyes misted with tears when the young Dion sang a ballad about an Irish mother in his clear and syrupy tenor .