sub·stan·tial / səbˈstanchəl/ • adj. 1. of considerable importance, size, or worth: a substantial amount of cash. ∎  strongly built or made: a row of substantial Victorian villas. ∎  (of a meal) large and filling. ∎  important in material or social terms; wealthy: a substantial Devon family.2. concerning the essentials of something: there was substantial agreement on changing policies.3. real and tangible rather than imaginary: spirits are shadowy, human beings substantial.DERIVATIVES: sub·stan·ti·al·i·ty / -ˌstanchēˈalitē/ n.

SUBSTANTIAL

Of real worth and importance; of considerable value; valuable. Belonging to substance; actually existing; real; not seeming or imaginary; not illusive; solid; true; veritable.

The right to freedom of speech, for example, is a substantial right.