Etymology
Early attestations (starting in 1624) are from North America, but the term was probably in local use in Britain earlier. The etymology is not entirely certain; it is probably a fusion of Middle English swam (“swamp, muddy pool, bog, marsh”, also “fungus, mushroom”) — from Old English swamm (“mushroom, fungus, sponge”), from Proto-West Germanic *swamm, from Proto-Germanic *swambaz, *swammaz — and Middle English sompe (“marsh, morass”), from either Middle Dutch somp, sump (“marsh, swamp”) or Middle Low German sump (“marsh, swamp”) (from Old Saxon *sump (“swamp, marsh”)), both from Proto-West Germanic *sump, from Proto-Germanic *sumpaz. *Swambaz, *swammaz and *sumpaz are likely related to each other, but it is unclear whether they are of Indo-European origin or are substrate words or wanderwo