someone who's main aim, target and wishes and ability is to harm unarmed civilians under the very specific will of causing grief, panic, or war-awakening.
good enough definition?
Source:
List of Irgun attacks - Wikipedia, the free encyclopedia from 1944-48 under Begin's leadership. These are the civilian targets.
1946, October 31 Bombing of the British Embassy in Rome. Nearly half the building was destroyed and 3 people were injured. [33]
1947, September 26 4 British policemen killed in Irgun bank robbery. [34]
1947, December 11 13 killed in attack on Tireh, near Haifa [38]
1947, December 12 20 killed, 5 wounded by barrel bomb at Damascus Gate. [39]
1947, December 13 6 killed, 25 wounded by bombs outside Alhambra Cinema. [40]
1947, December 13 5 killed, 47 wounded by two bombs at Damascus Gate. [40]
1947, December 13 7 killed, 10 seriously injured in attack on Yehudiya. [40]
1947, December 16(ca) 10 killed by bomb at Noga Cinema in Jaffa. [41]
1947, December 29 14 Arabs killed by bomb in Jerusalem. [34][42]
1947, December 30 6 Arabs killed and, 42 injured by grenades at Haifa refinery, precipitating the Haifa Oil Refinery massacre, which lead to the Balad al-Shaykh massacre. [43]
1948, January 1 2 Arabs killed and 9 injured by shooting attack on cafe in Jaffa. [44]
1948, January 5 14 Arabs killed and 19 injured by truck bomb outside the 3-storey 'Serrani', Jaffa's built Ottoman Town Hall [45]
1948, January 7 20 Arabs killed by bomb at Jaffa Gate. [46][47]
1948, February 10 7 Arabs killed near Ras el Ain after selling cows in Tel Aviv [48]
1948, February 18 12 Arabs killed and 43 wounded at a marketplace in Ramla [49]
I think that qualifies under the definition.