Foam or bubbles created by soap or detergent mixing with water, especially when washing.
From Middle Dutch 'sudse' or Old Norse roots meaning 'marsh' or 'swamp.' The term shifted to mean soap foam because the bubbles resembled marsh water or muddy liquid.
Suds were so important to history that 'soap' became a verb, and studying how different water types make different suds was cutting-edge chemistry in the 1800s—hard water destroys soap's foaming ability!
Complete word intelligence in one call. Free tier — 50 lookups/day.