speculation

noun

1.
a message expressing an opinion based on incomplete evidence
Derived from:
speculate
2.
a hypothesis that has been formed by speculating or conjecturing (usually with little hard evidence)
Derived from:
speculate
3.
an investment that is very risky but could yield great profits
Derived from:
speculate
4.
continuous and profound contemplation or musing on a subject or series of subjects of a deep or abstruse nature
Derived from:
speculate