Let's agree on some definitions:
1) intervention or event + loss of life = killing
2) killing (1) + of a human + by a human = homicide
3) homicide (2) + premeditation + malice = murder
In the abortion case:
- an intervention takes place resulting in loss of life = an organism is killed (1)
- the organism being killed is human. the intervention is done by a human = a homicide (2)
Now, is it murder? it's as homicide (human killed by human) and it's premeditated. But is there malice? It depends.
Sometimes loss of life is inevitable. Sometimes it is done as a form of euthanasia or eugenics. Sometimes the pregnancy was accidental or involuntary. Sometimes it's due to economic reasons. Sometimes it's simply due to personal preferences or a state of mind... etc.
You can analyze the situation to establish whether the abortion (i.e.: homicide with premeditation) has malice or not, and whether you want to call it "murder" from a moral standpoint. But it remains a homicide with premeditation and should not be taken lightly.
For example, if the reason behind an abortion is solely to kill someone with Down syndrome, I would say there's malice there (eugenics is wrong). A person with Down syndrome is as worthy of life as everyone else, yet they are a frequent target of abortions. Likewise, in some cultures, male offspring is associated with prosperity and are preferred over females, even resulting in abortions based solely on sex. That's also another form of malice.
But if you want to feel happy with yourself and engage into "terminology gerrymandering" (e.g.: it's not alive, it's not a human, it's not a separate organism) or "terminology laundering" (e.g.: it's too small to be a homicide = structuring/smurfing), you'll be only playing yourself. The earlier in life you accept that reality is messed up, and that unfortunate things happen, while valuing human life, the better.
If you want to mix politics, religion, society, medicine, economics, etc. into a big ball of spaghetti resulting in endless arguing in a limbo of unhappy yelling people, you can also do that, but beware that many clever people will take advantage of you in the process. Ultimately, it's your life and you can spend your days as you see fit.