conjecture on (something)
To speculate or wonder about something. A murmur went through the stands as people conjectured on which dog would be named the winner.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
conjecture on something
to speculate on or guess about something. I will not even conjecture on the outcome. Dave conjectured on what might happen next.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.