ponderyoudaoicibaDictYouDict[ponder 词源字典]
ponder: [14] To ponder something is etymologically to ‘weigh’ it up. The word comes via Old French ponderer from Latin ponderāre ‘weigh’, hence ‘consider’ (source also of English preponderate [17]). This was derived from pondus ‘weight’ (source of English ponderous [14]), a relative of pendere ‘weigh’ (source of English compendium [16], compensate [17], dispense, expense, pansy, pension [14], pensive [14], peseta [19], poise [15], and spend) and pendēre ‘hang’ (from which English gets pendant, pendulum, etc).

Also closely related is English pound, the unit of weight.
=> compendium, compensate, dispense, expense, pansy, pendant, pendulum, pension, pensive, peseta, poise, pound, preponderate, spend[ponder etymology, ponder origin, 英语词源]
ponder (v.)youdaoicibaDictYouDict
early 14c., "to estimate the worth of, to appraise," from Old French ponderer "to weigh, poise" (14c., Modern French pondérer) and directly from Latin ponderare "ponder, consider, reflect," literally "to weigh," from pondus (genitive ponderis) "weigh" (see pound (n.1)). Meaning "to weigh a matter mentally" is attested from late 14c. Related: Pondered; pondering; ponderation.