"Hear, O Israel: The LORD our God [is] one LORD" (Deuteronomy 6:4)"One" is related to the prefix 'uni-', which we see in "universe", "unity", "union", etc.
"Endeavouring to keep the unity of the Spirit in the bond of peace. [There is] one body, and one Spirit, even as ye are called in one hope of your calling; One Lord, one faith, one baptism, One God and Father of all, who [is] above all, and through all, and in you all. But unto every one of us is given grace according to the measure of the gift of Christ." (Ephesians 4:3-7)