Thesaurus.com
Dictionary.com
Definitions

substantial

[suhb-stan-shuhl] / səbˈstæn ʃəl /
ADJECTIVE
important, ample
Synonyms
STRONGEST
big consequential considerable extraordinary generous hefty large massive meaningful serious significant sizable solid steady strong valuable vast
STRONG
material
WEAK
abundant big-deal bulky durable firm goodly heavy heavyweight key major-league momentous plentiful principal sound stable stout sturdy superabundant tidy weighty well-built worthwhile
Antonyms
STRONGEST
broken inconsiderable insignificant intermittent little meaningless miniature minor selfish slight small soft tiny trivial unimportant untrustworthy useless weak worthless
WEAK
ethereal impoverished mental poor spiritual unsubstantial
ADJECTIVE
material, real
Synonyms
STRONGEST
actual material positive real solid
WEAK
card-carrying concrete corporeal existent for real honest-to-God honest-to-goodness legit objective phenomenal physical righteous sensible sure-enough tangible true valid visible weighty
Antonyms
WEAK
ethereal impoverished insignificant little mental minor poor small spiritual unimportant unsubstantial
ADJECTIVE
rich
Synonyms
STRONGEST
solid
WEAK
affluent comfortable easy opulent prosperous snug solvent wealthy well well-heeled well-off well-to-do
Antonyms
WEAK
ethereal impoverished insignificant little mental minor poor small spiritual unimportant unsubstantial

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

UnitedHealth highlighted changes made under Hemsley’s tenure, including replacing almost half of the company’s top 100 executives and making substantial artificial intelligence investments.

From The Wall Street Journal • Apr. 21, 2026

Jones had substantial input into the design of his statue, choosing the pose and offering other guidance.

From Los Angeles Times • Apr. 21, 2026

“We see the signing of this EO as a substantial step towards diminishing regulatory risk in this emerging class of therapies, enabling investor comfort,” RBC Capital Markets analyst Brian Abrahams told investors.

From MarketWatch • Apr. 20, 2026

"The substantial amount of time that passed between her death and the discovery meant that crucial evidence had degraded or disappeared."

From Barron's • Apr. 20, 2026

But right now he wanted something a lot more substantial than a cell phone to hold on to: a phone rooted in concrete, maybe.

From "Found" by Margaret Peterson Haddix

Vocabulary lists containing substantial

The Vocabulary.com Top 1000

Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!

The SAT: Multiple-Meaning Words, List 2

Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!

The Real Deal: Synonyms for "True"

Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!