A substantive in the genitive limits the meaning of a substantive on which it depends.1291
The genitive limits for the time being the scope of the substantive on which it depends by referring it to a particular class or description, or by regarding it as a part of a whole. The genitive is akin in meaning to the adjective and may often be translated by an epithet. Cp. στέφανος χρυ_σίου with χρυ_σοῦς στέφανος, φόβος πολεμίου with πολέμιος φόβος, τὸ εὖρος πλέθρου with τὸ εὖρος πλεθριαῖον ( cross1035). But the use of the adjective is not everywhere parallel to that of the genitive.1292
In poetry a genitive is often used with βία_, μένος, σθένος
In poetry δέμας
σφενδονητῶν πάμπολύ τι χρῆμα
The genitive with substantives denotes in general a connection or dependence between two words. This connection must often be determined (1) by the meaning of the words, (2) by the context, (3) by the facts presupposed as known ( cross1301). The same construction may often be placed under more than one of the different classes mentioned below; and the connection between the two substantives is often so loose that it is difficult to include with precision all cases under specific grammatical classes.
a. The two substantives may be so closely connected as to be equivalent to a single compound idea: τελευτὴ τοῦ βίου ‘life-end’ (cp.
b. The genitive with substantives has either the attributive ( cross1154), or, in the case of the genitive of the divided whole ( cross1306), and of personal pronouns ( cross1185), the predicate, position ( cross1168).1296
Words denoting number, especially numerals or substantives with numerals, often agree in case with the limited word instead of standing in the genitive:
φόρος τέσσαρα τάλαντα
Herbert Weir Smyth [n.d.], A Greek Grammar for Colleges; Machine readable text [info] [word count] [Smyth].