Play word 活き締め 活き締め いきじめ draining blood from a live fish (from above the gills and at the base of the tail) to keep it fresh
Play word 活け締め 活け締め いけじめ draining blood from a live fish (from above the gills and at the base of the tail) to keep it fresh
Play word 活人剣 活人剣 かつじんけん life-saving sword (a killing sword may be a sword of life depending on how it is used)
Play word 活性酸素 活性酸素 かっせいさんそ reactive oxygen (i.e. free radicals, which can be destructive at high concentrations)