Allaah is your Rabb. He owns everything and those whom you call upon besides Him do not even own the white stringy-sand on a datestone (such a minute posession) [Faatir 35:13]

Ibn al-Qayyim explains that some of Allaah's Names are related to His Ruboobiyyah and are more specific than the name Ar-Rabb. For example: Ar-Razzaaq (the Provider), al-Muhyee (the One Who gives life). Likewise, there are certain actions which are related to His Ruboobiyyah and are more specific than the name ar-Rabb. For example: sending down the rain, splitting the seed, giving someone honour, lowering someone, guiding or misguiding someone etc. (Al-Madarij)

Uloohiyyah : A term denoting that Allaah is the only One to Whom all forms of worship should be directed in truth, whether actions of the heart (feelings), words and statements and actions of the limbs. The word ilaah is derived from it meaning: Something that is adored, worshipped turned to i.e. an object of worship, subservience and adoration. There is nothing besides Allaah who is deserving of that and this is the meaning of the testimony Laa ilaaha illallaaha (There is no Ilaah which is deserving of any form of worship except Allaah alone), the truth and certainty of which every messenger came to establish. Allaah Azzawajall says:

Your Ilaah is but one Ilaah [Nahl 16:20]

And He alone is the Ilaah in the Heavens and the Ilaah in the Earth [Zukhroof 43:84]