Ponder

ponder
verb

To think or think about carefully and at length: chew on or over , cogitate, consider, contemplate, deliberate, entertain, excogitate, meditate, mull, muse, reflect, revolve, ruminate, study, think, think out, think over, think through, turn over, weigh. Idioms: cudgel one's brains, put on one's thinking cap, rack one's brain. See thoughts

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