μέτρον metron

That which measures, or that which is measured: a measure, a measuring vessel or rod, and figuratively a standard or allotted amount. With a genitive of the thing measured it names the measure of that thing (Rom 12:3, μέτρον πίστεως; also 2 Cor 10:13; Eph 4:7, 13, 16). Other phrases include ἐκ μέτρου, by measure (John 3:34). Whether μέτρον πίστεως in Rom 12:3 is a quantity of faith or an allotted sphere is not settled by the noun alone; both a measured amount and a measuring standard are attested uses.