Fasting is referred to as Sawm or Saom (صوم) or siyam (صيام) in Arabic. Literally, fasting means abstaining from talking, eating and drinking etc, and an individual that refrain from these things, he is considered as Saaim (the observer of fast).
In Shari’ah, fasting mean “to worship Allah by abstaining, with intention to please Him, from food, drink, and sexual intercourse or an intentional and lustful discharge of semen from the period between the break of dawn until sundown”. Similarly, Sheikh Muhammed Salih Al-Munajjid explain that Siyaam (fasting) means abstaining from things that break the fast, from dawn until sunset, having first made the intention (niyyah) to fast. 70 Matters Related to Fasting Al-Siyaam. Therefore, fasting means to worship Allah by abstaining, with intention to please Him, from things that break the fast, from dawn (Fajr) until sunset (Magrib).
Corroborated by authentic narrations, abstaining from things that break the fast includes; abstaining from food, drinks, and from indulging in things that can vitiate the fast through private parts, other body parts, the heart and mind. Fasting is an act of worship that believers and nonbelievers generally regard as a mean of attaining highest state of spirituality.
Fasting is a soul discipline act of worship that carries an exceptional moral and spiritual distinctive of Islam; it helps the observer to develop self-control and suppress his/her passions and desires for Allaah’s command; the spirit of patience whilst fasting helps in strengthening observer’s faith; the observer of fast who abstains from permissible things is likely to stay away from prohibited things and feel conscious of his/her sins; it trains the soul of the observer to endure hunger and thirst, and habituates it to be patient, and entertain the same sense of the needy, thus, greater compassion towards the deprived is gained whilst fasting etc.