What that specific word that can be replaced in Arabic for the word "The God" for a common term?
Allah الله is one of 99 names of God - the almighty, the creator - (SWT).
The correct translation of God is إله. It is written إله but pronounced إلاه (ilaah).
ِAlso آلهة is another possible transition of God.
Example إله:
وَإِلَٰهُكُمْ إِلَٰهٌ وَاحِدٌ ۖ لَّا إِلَٰهَ إِلَّا هُوَ الرَّحْمَٰنُ الرَّحِيمُ
سورة البقرة، آية 163
And your god is one God. There is no deity [worthy of worship] except Him, the Entirely Merciful, the Especially Merciful.
Surat Al-Baqara, verse 163.
Example آلهة:
And We made firm their hearts when they stood up and said, "Our Lord is the Lord of the heavens and the earth. Never will we invoke besides Him any deity. We would have certainly spoken, then, an excessive transgression (14) These, our people, have taken besides Him deities. Why do they not bring for [worship of] them a clear authority? And who is more unjust than one who invents about Allah a lie?" (15)
Al-Kahf, verses 14 & 15
وَرَبَطْنَا عَلَىٰ قُلُوبِهِمْ إِذْ قَامُوا فَقَالُوا رَبُّنَا رَبُّ السَّمَاوَاتِ وَالْأَرْضِ لَن نَّدْعُوَ مِن دُونِهِ إِلَٰهًا ۖ لَّقَدْ قُلْنَا إِذًا شَطَطًا (14) هَٰؤُلَاءِ قَوْمُنَا اتَّخَذُوا مِن دُونِهِ آلِهَةً ۖ لَّوْلَا يَأْتُونَ عَلَيْهِم بِسُلْطَانٍ بَيِّنٍ ۖ فَمَنْ أَظْلَمُ مِمَّنِ افْتَرَىٰ عَلَى اللَّهِ كَذِبًا (15)
سورة الكهف، آية 14 و 15
Another word is رب which means Lord or Owner. This can be used for human-being, unlike إله, which is only used to refer to God.
الْحَمْدُ لِلَّهِ رَبِّ الْعَالَمِينَ
سورة الفاتحة، آية 2
All praise is due to Allah, Lord of the worlds
Al-Faatiha, verse 2