Antonyms of adj economical

2 of 3 senses of economical

Sense 1
economic, economical -- (using the minimum of time or resources necessary for effectiveness; "an economic use of home heating oil"; "a modern economical heating system"; "an economical use of her time")

INDIRECT (VIA efficient) -> inefficient -- (not producing desired results; wasteful; "an inefficient campaign against drugs"; "outdated and inefficient design and methods")

Sense 3
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")

INDIRECT (VIA thrifty) -> wasteful -- (tending to squander and waste)

Similarity of adj economical

3 senses of economical

Sense 1
economic, economical -- (using the minimum of time or resources necessary for effectiveness; "an economic use of home heating oil"; "a modern economical heating system"; "an economical use of her time")
       => efficient (vs. inefficient) -- (being effective without wasting time or effort or expense; "an efficient production manager"; "efficient engines save gas")

Sense 2
economic, economical -- (of or relating to an economy, the system of production and management of material wealth; "economic growth"; "aspects of social, political, and economical life")

Sense 3
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")
       => thrifty (vs. wasteful) -- (careful and diligent in the use of resources)