Adjective wasteful has 3 senses
  1. uneconomical, wasteful - inefficient in use of time and effort and materials; "a clumsy and wasteful process"; "wasteful duplication of effort"; "uneconomical ebb and flow of power"
    Antonym: efficient (indirect, via inefficient)
  2. wasteful - tending to squander and waste
    thrifty, economical, frugal, scotch, sparing, stinting, penny-wise, saving, scavenging
  3. wasteful - laying waste; "when wasteful war shall statues overturn"- Shakespeare
    constructive (indirect, via destructive)