Merriam-Webster defines terrorism as:
the systematic use of terror especially as a means of coercion
and the definition of terror is:
1: a state of intense fear
2 a: one that inspires fear : scourge b: a frightening aspect
3: reign of terror
4: violent or destructive acts (as bombing) committed by groups in order to intimidate a population or government into granting their demands
So murdering a doctor in order to intimidate other doctors and government officials into outlawing abortion is an act of terrorism. Publishing the names and addresses of doctors and clinic workers so that they fear for their lives and safety and cannot perform the job that you hate is an act of terrorism. It is "using a destructive act in order to intimidate a population or government into granting their demands" and "the systematic use of terror especially as a means of coercion".
But maybe you fucksticks need more. Certainly I've heard a a bunch of talking heads whine about how this is "just a murder, not an act of terrorism according to the law".
So let's look at how the US federal law defines a terrorism:
As used in this section—
(1) the term “international terrorism” means terrorism involving citizens or the territory of more than 1 country;
(2) the term “terrorism” means premeditated, politically motivated violence perpetrated against noncombatant targets by subnational groups or clandestine agents;
(3) the term “terrorist group” means any group, or which has significant subgroups which practice, international terrorism;
(4) the terms “territory” and “territory of the country” mean the land, waters, and airspace of the country; and
(5) the terms “terrorist sanctuary” and “sanctuary” mean an area in the territory of the country—
(A) that is used by a terrorist or terrorist organization—
(i) to carry out terrorist activities, including training, fundraising, financing, and recruitment; or
(ii) as a transit point; and
(B) the government of which expressly consents to, or with knowledge, allows, tolerates, or disregards such use of its territory and is not subject to a determination under—
(i) section 2405(j)(1)(A) of the Appendix to title 50;
(ii) section 2371 (a) of this title; or
(iii) section 2780 (d) of this title.
(bolds mine again)
Neither the legal nor the English definition of terrorism include phrases like scary Islamofascist or dark skinned foreigner. Terrorism is not a crime committed only by people of a certain race or ethnicity or religious persuasion (though if you can find an atheist terrorist group I'll eat my shoe). Terrorism is very simply an act of violence committed by a non governmental group or person in order to intimidate or coerce.
The person that killed Dr. Tiller is a terrorist. The groups that organize to terrorize doctors and nurses and clinic staff by publishing their addresses are terrorists. The people who recruit others into doing violence (I'm talking to you Bill O'Reilly and Michelle Malkin) are terrorists. Eric Rudolf was a terrorist.
So was Timothy McVeigh. So are the right wing militia groups plotting to violently overthrow the government.
If you don't like being called a terrorist, then stop using or excusing or promoting acts of violence meant to intimidate or coerce the population into doing your will.