substantial

adj. sustancial, considerable, substancial; físico, corpóreo; sustancioso, enjundioso, substancioso

sustancial | considerable | importante | sólido | grande

insubstancial, insustancial

Ex: This data base will eventually become a very substantial bibliographic data base.
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*insubstantial = insustancial, poco sólido, frágil

(adj.) = sustancial, importante, considerable, sustancioso
Ex: This data base will eventually become a very substantial bibliographic data base.
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* insubstantial = insustancial, poco sólido, frágil