proslaveryEtymologyFrom pro- + slavery.adjSupporting slavery.“By 1835 the excitement was at its height, and especially along the line of the moral and religious argumentation, where the proslavery men met talk with talk.”nounSupport for the institution of slavery.“The old wisdom that southerners rose up in unison in 1831 after a decade of preparation in the tenets of proslavery is patently an erroneous interpretation.”