What does the medical terminology combining form a- mean?

The combining form "a-" in medical terminology generally means "without," "lack of," or "absence of."

Here are some examples:

* Anemia: Lack of red blood cells or hemoglobin.

* Analgesia: Absence of pain.

* Aphasia: Loss of the ability to speak.

* Aphagia: Inability to swallow.

* Asexual: Lack of sexual attraction.

It's important to note that the meaning of "a-" can vary depending on the context. For example, in the term "asymptomatic," "a-" means "without" symptoms, while in "athetosis," "a-" means "not" normal movement.

Always refer to a medical dictionary or terminology resource to confirm the specific meaning of "a-" in a particular term.