American Heritage Dictionary
(4)
Century Dictionary
(5)
GNU Webster's 1913
(2)
WordNet
(4)
Elsewhere on the web
And I thought it was astonishing to speculate, as if this were a competition, on something that was such a fresh wound.— David Rockwell builds at Ground Zero
I used the word speculate, because that is what it is speculation.— MyLinkVault Newest Links
We do not know and cannot speculate, and are in dangerous territory when we-or anyone else for that matter-claim to have iron-clad categorical answers to these thoroughly modern questions.— The Chicago Blog
'' They speculate, they ponder, they prattle in polemics.
In the absence of knowledge, we're left to speculate -- and speculate I will!— Arms and influence

American Heritage Dictionary (1)
Century Dictionary (1)
Bubble size: how much this word was used in a year
Bubble height: used more or less than expected, vs. all uses evenly distributed
You can expect to see this word about twice a week.