I'm supposed to be there at ten. He was supposed to go to the store.
source: WordNet 3.0
mistakenly believed
The supposed existence of ghosts.
source: WordNet 3.0
doubtful or suspect
These so-called experts are no help.
source: WordNet 3.0
based primarily on surmise rather than adequate evidence
Theories about the extinction of dinosaurs are still highly conjectural. The supposed reason for his absence. Suppositious reconstructions of dead languages. Hypothetical situation.