What do non-trinitarians mean when they call Jesus the "Son of God"?

On a different question I got an answer and some comments. One of which said: > Generally, when a Christian says that Jesus is the "Son of God" they are referring to the doctrine of the Trinity, where Jesus is a person of a three-part godhead. It's a complicated doctrine that necessitates antinomy. As for your friend's reasoning, it is sound, and is the same reason we call Adam, from Genesis, the son of God also, for he also had no human father, instead God fashioned him from the clay of the Earth and breathed life into him. – fredsbend yesterday If that is what Trinitarians usually mean when they call Jesus the "Son of God", what do non-trinitarians mean when they say it?