an agreement to risk money etc on an event of which the result is doubtful

game of chance; money gambled

(to make) a conclusion, opinion, based on incomplete evidence

speculation, assumption

(an attempt or activity with) a risk of loss or a chance of profit; to play games to try to win money

chance, speculation

to form an opinion, give an answer, make a statement about (something) that is not based on very careful thought, calculation or definite knowledge

belief, speculation

an idea, suggestion, put forward as a starting-point for reasoning or an explanation

theory

something which seems likely although there is no proof; arrogance (the usual word)

belief, hypothesis

(an instance of) a possibility or chance (of meeting danger, suffering loss, injury etc)

chance taken

(an instance of) speculating; (a business deal as a result of) speculating

theory, guess

the act of supposing something to be true but without proof; a guess

guess, belief