An "old boyfriend" simply means a man who was previously in a romantic relationship with a woman, but that relationship has ended.
In more detail:
- "Old" in this context refers to the past relationship. It indicates that the person was once her boyfriend, but is no longer in that role.
- "Boyfriend" signifies a romantic partner. The relationship involved a degree of commitment and affection, typically more than just friendship.
Therefore, an "old boyfriend" is an ex-boyfriend – someone who was a romantic partner in the past. The duration of the past relationship and the circumstances of its ending are not implied by the term "old boyfriend" itself. The term is neutral and provides no further details beyond the fact of a former romantic connection.