The most credible is a derivation from the Mi'kmaq word for river, "Seboo.
"[1] The river flows out of a chain of lakes near the border with Annapolis County, named respectively, First, Second, Third, Fourth, Fifth, Sixth, Seventh, Eighth and Ninth Lakes.
The Sissiboo River follows a winding course, draining a large area and passing through the former lumbering communities of Weymouth Falls and Weymouth Mills.
An inactive Dominion Atlantic Railway bridge was demolished in 2012.
Further downstream, Highway 101 crosses near the fishing community of New Edinburgh.