Толковый словарь английского языка Oxford English Reference - speculation

n. 1 the act or an instance of speculating; a theory or conjecture (made no speculation as to her age; is given to speculation). 2 a a speculative investment or enterprise (bought it as a speculation). b the practice of business speculating. 3 a game in which trump cards are bought or sold. Etymology: ME f. OF speculation or LL speculatio (as SPECULATE)