stereos describes firmness, whether of a foundation, steadfast resistance, or food for the mature.

The attested uses describe something firm or substantial: steadfastness in resistance and a foundation that stands, alongside food characterized as suitable for the mature.

1. Firmness in standing or resisting · dominant

   In 1 Peter 5:9, the nominative plural masculine form qualifies those opposing an adversary in faith; the APB renders the clause “Oppose him, strong in the faith.” In 2 Timothy 2:19, the nominative singular masculine form describes God’s foundation as standing; the APB renders “the strong foundation of God stands.”

   1 Peter 5:92 Timothy 2:19
2. Substantial food for the mature · common

   In Hebrews 5:12, the genitive singular feminine form occurs in the contrast between milk and food; the APB renders “milk, not of solid food.” In Hebrews 5:14, the nominative singular feminine form describes the food assigned to the mature; the APB renders “solid food is for the mature.”

   Hebrews 5:12Hebrews 5:14

In the Anselm Project Bible: The APB uses “strong” in the resistance and foundation clauses and “solid” in the food clauses. These renderings confirm the verse-level contrasts rather than establish separate English equivalents.