1.FECKLESS(ADJECTIVE):without purpose
Synonyms: aimless, carefree
Antonyms: purposeful, efficient
Example Sentence:It was a feckless attempt to make the company a success.
2.MERCURIAL(ADJECTIVE):flighty, temperamental
Synonyms: changeable, impulsive
Antonyms: constant, stable
Example Sentence:His mercurial temperament made him difficult to work with his teammates.
3.SPECIOUS (ADJECTIVE):misleading
Synonyms: deceptive, false
Antonyms: genuine, valid
Example Sentence:His readings are seeming to be specious.
4.QUIXOTIC(ADJECTIVE): idealistic
Synonyms: impractical, dreamy
Antonyms: realistic, sensible
Example Sentence:It was clearly a quixotic case against the defendant.
5.DISINGENUOUS(ADJECTIVE):Not straightforward or candid
Synonyms: unfair, cunning
Antonyms: frank, truthful
Example Sentence:It was disingenuous of her to claim she had no financial interest in the company.
6.DERISIVE (ADJECTIVE):ridiculing
Synonyms: cheeky,mocking
Antonyms:polite, respectful
Example Sentence:It was a derisive act.
7.ODIOUS(ADJECTIVE): extremely unpleasant
Synonyms: disgusting, horrid
Antonyms: attractive, delightful
Example Sentence:The detective said it was the most odious crime she had ever seen.
8.FORTUITOUS (ADJECTIVE):lucky, accidental
Synonyms: random, chance
Antonyms: intentional, planned
Example Sentence:The check could not have arrived at a more fortuitous time.
9.RAPACIOUS (ADJECTIVE):aggressively greedy or ravenous
Synonyms:ferocious, marauding
Antonyms: satisfied, contended
Example Sentence:He is a rapacious lawyer.
10.HALCYON (ADJECTIVE):calm, peaceful
Synonyms:quiet, still
Antonyms: agitated
Example Sentence:It is such a halcyon place.