How to Say "substantial" in Spanish
The most common Spanish word for “substantial” is “generoso” — use 'generoso' when referring to a 'substantial' portion or amount of something, especially food or a gift, implying it's more than expected or a good size..
generoso
heh-neh-ROH-soh/xe.neˈɾo.so/

Examples
El camarero nos sirvió un trozo de pastel muy generoso.
The waiter served us a very generous slice of cake (a large one).
Recibimos una donación generosa para nuestro proyecto de investigación.
We received a generous donation (a large amount) for our research project.
Using 'Generoso' for Things
When 'generoso' describes a thing (like a portion or a budget), it means the amount is large or plentiful. It carries the same positive feeling as describing a person.
respetable
/rreh-speh-TAH-bleh//respeˈtaβle/

Examples
Había una cantidad respetable de gente en el concierto.
There was a considerable amount of people at the concert.
Llevaban una velocidad respetable.
They were traveling at a substantial speed.
Generoso vs. Respetable
Related Translations
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