Terrorism is usually defined by the domestic law of the jurisdiction in which the crime was committed.
Article 6 Genocide comes in different flavors and defined by the elements of the offense:
Article 6 Genocide
Introduction
With respect to the last element listed for each crime:
(a) The term “in the context of” would include the initial acts in an emerging pattern;
(b) The term “manifest” is an objective qualification;
(c) Notwithstanding the normal requirement for a mental element provided for in article 30, and recognizing that knowledge of the circumstances will usually be addressed in proving genocidal intent, the appropriate requirement, if any, for a mental element regarding this circumstance will need to be decided by the Court on a case-by-case basis.
Article 6
(a) Genocide by killing
Elements
1. The perpetrator killed2 one or more persons.
2. Such person or persons belonged to a particular national, ethnical, racial or religious group.
3. The perpetrator intended to destroy, in whole or in part, that national, ethnical, racial or religious group, as such.
4. The conduct took place in the context of a manifest pattern of similar conduct directed against that group or was conduct that could itself effect such destruction.
Article 6 (b)
Genocide by causing serious bodily or mental harm
Elements
1. The perpetrator caused serious bodily or mental harm to one or more persons.
2. Such person or persons belonged to a particular national, ethnical, racial or religious group.
3. The perpetrator intended to destroy, in whole or in part, that national, ethnical, racial or religious group, as such.
4. The conduct took place in the context of a manifest pattern of similar conduct directed against that group or was conduct that could itself effect such destruction.
Article 6 (c)
Genocide by deliberately inflicting conditions of life calculated to bring about physical destruction
Elements
1. The perpetrator inflicted certain conditions of life upon one or more persons.
2. Such person or persons belonged to a particular national, ethnical, racial or religious group.
3. The perpetrator intended to destroy, in whole or in part, that national, ethnical, racial or religious group, as such.
4. The conditions of life were calculated to bring about the physical destruction of that group, in whole or in part.
5. The conduct took place in the context of a manifest pattern of similar conduct directed against that group or was conduct that could itself effect such destruction.
Article 6 (d)
Genocide by imposing measures intended to prevent births
Elements
1. The perpetrator imposed certain measures upon one or more persons.
2. Such person or persons belonged to a particular national, ethnical, racial or religious group.
3. The perpetrator intended to destroy, in whole or in part, that national, ethnical, racial or religious group, as such.
4. The measures imposed were intended to prevent births within that group.
5. The conduct took place in the context of a manifest pattern of similar conduct directed against that group or was conduct that could itself effect such destruction.
Article 6 (e)
Genocide by forcibly transferring children
Elements
1. The perpetrator forcibly transferred one or more persons.
2. Such person or persons belonged to a particular national, ethnical, racial or religious group.
3. The perpetrator intended to destroy, in whole or in part, that national, ethnical, racial or religious group, as such.
4. The transfer was from that group to another group.
The conduct took place in the context of a manifest pattern of similar conduct directed against that group or was conduct that could itself effect such destruction.