The Collaborative International Dictionary
mull over
mull over \mull over\, v. t. To think about; to consider; to ruminate about; as, mull it over and decide in the morning. [Colloq. U.S.]
Wiktionary
mull over
vb. To think deeply about something; to ponder, deliberate or ruminate.
WordNet
mull over
v. reflect deeply on a subject; "I mulled over the events of the afternoon"; "philosophers have speculated on the question of God for thousands of years"; "The scientist must stop to observe and start to excogitate" [syn: chew over, think over, meditate, ponder, excogitate, contemplate, muse, reflect, mull, ruminate, speculate]