plural of viral envelope

plural of work envelope

plural of double envelopment

(military) pincer attack

plural of convex envelope

(mathematical analysis, of a set) Convex hull.

plural of concave envelope

(mathematics, optimisation theory, of a function on a set) For a given set S⊆ℝⁿ and real-valued function f defined on the convex hull conv(S), the lowest-valued concave function that overestimates or equals f over S.

plural of padded envelope

A large thick envelope, now usually coated with foam or bubblewrap, used to protect fragile items in the mail.