2. To disqualify or try to disqualify someone from taking part in a decision because of a possible prejudice or personal involvement: "The professor was definitely recusing himself from taking part in the legal action against a company because he was once an employee there."
3. Etymology: "derived from the Middle French word recuser, which came from Latin recusare, "to refuse".
"English speakers started using recuse with the meaning "to refuse" or "to reject" in the 14th century. By the 15th century, the term meant "to challenge" or "to object to (a judge)". The current legal use of recuse as a term specifically meaning "to disqualify (oneself) as a judge" didn't come into general use until the mid-20th century.
Now, the more inclusive applications come from the sense of recusing oneself from such things as debates and decisions; as well as, legal cases in courts of law.