The word w = [x i1 , x i2 , . . . , x i k ] is a simple commutator word if k ≥ 2, i 1 = i 2 and i j ∈ {1, . . . , m}, for some m > 1. For a finite group G, we prove that if i 1 = i j for every j = 1, then the verbal subgroup corresponding to w is nilpotent if and only if |ab| = |a||b| for any w-values a, b ∈ G of coprime orders. We also extend the result to a residually finite group G, provided that the set of all w-values in G is finite.