Antonyms of adj wasteful

3 senses of wasteful

Sense 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")

INDIRECT (VIA inefficient) -> efficient -- (being effective without wasting time or effort or expense; "an efficient production manager"; "efficient engines save gas")

Sense 2
wasteful (vs. thrifty) -- (tending to squander and waste)

thrifty (vs. wasteful) -- (careful and diligent in the use of resources)
        => economical, frugal, scotch, sparing, stinting -- (avoiding waste; "an economical meal"; "an economical shopper"; "a frugal farmer"; "a frugal lunch"; "a sparing father and a spending son"; "sparing in their use of heat and light"; "stinting in bestowing gifts"; "thrifty because they remember the great Depression"; "`scotch' is used only informally")
        => penny-wise -- (thrifty in small matters only)
        => saving -- (characterized by thriftiness; "wealthy by inheritance but saving by constitution"- Ellen Glasgow)

Sense 3
wasteful -- (laying waste; "when wasteful war shall statues overturn"- Shakespeare)

INDIRECT (VIA destructive) -> constructive -- (constructing or tending to construct or improve or promote development; "constructive criticism"; "a constructive attitude"; "a constructive philosophy"; "constructive permission")

Similarity of adj wasteful

3 senses of wasteful

Sense 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")
       => inefficient (vs. efficient) -- (not producing desired results; wasteful; "an inefficient campaign against drugs"; "outdated and inefficient design and methods")

Sense 2
wasteful (vs. thrifty) -- (tending to squander and waste)
       => extravagant, prodigal, profligate, spendthrift -- (recklessly wasteful; "prodigal in their expenditures")
       => pound-foolish -- (unwise in dealing with large sums)
       => uneconomical, uneconomic -- (wasteful of resources)
          Also See-> improvident#1

Sense 3
wasteful -- (laying waste; "when wasteful war shall statues overturn"- Shakespeare)
       => destructive (vs. constructive) -- (causing destruction or much damage; "a policy that is destructive to the economy"; "destructive criticism")