Allah= God (without equal or offspring)
Tawhid/Tawheed/Tauhid= Faith in one God
Aqeedah/Aqidah= The firm creed that one's heart is fixed upon without any wavering or doubt. It excludes any supposition, doubt or suspicion.
Ahkaam= Legal status in Islamic Law, Rulings.
The five kind rulings:
1.) Waajib or Fardh= Cumpulsory requirement
2.) Mustahabb= Recommended but not cumpulsory (often a sunnah/sunnan)
3.) Makruh= Disliked but not forbidden
4.) Muharram or more simply, Haraam= Forbidden
5.) Halaal= Lawful and Allowed
Qu'ran= the literal word of Allah taught to Muhammed His Prophet through the angel Jibreel (Gabriel)
Shirk=to associate partners with Allah---to practice shirk is to remove one's self from Islam and the mercy of Allah
S.W.T= When writing the name of Allah, Muslims often follow it with the abbreviation "SWT." These letters stand for the Arabic words "Subhanahu Wa Ta'ala," which translates to "Glory to Him, the Exalted." Muslims use these or similar words to glorify God when mentioning His name. Pronunciation: sub-han'-a-hoo wa ta a la
Muhammed= the last Prophet of Allah SWT from a long line of Prophets such as Jesus, Abraham, and Moses.
S.A.W= When writing the name of the Prophet Mohammed, Muslims often follow it with the abbreviation "SAW". These letters stand for the Arabic words "salla Allah alaihi wa sallam", meaning "may Allah's peace and blessings be upon him." It is a standard Muslim expression of love and respect for the Prophet. "May the peace and blessings of Allah be upon him" is usually said whenever the name of Prophet Muhammad (S.A.W.) is mentioned or read.
Bid'ah= An innovation to the practice of Islam, always haraam.
Daleel= Islamic evidence from either the Qu'ran or sahih ahadith (authentic, prophetic narrations).
Sahih/Saheeh= Authentic, usually in reference to hadith. It means the hadith has a direct chain of narration to the one who is said to be speaking.
Hadith/Hadeeth= a collected saying or action of the Prophet Mohammed S.A.W that has been recorded. If it is Sahih it is a form of daleel (proof).
Ahadith/Ahaadeeth= plural of hadith.
Kuffaar= those who practice polyethism and reject the idea of one God.