For reactions involving oxygen, the gain of oxygen implies the oxidation of the atom or molecule to which the oxygen is added (and the oxygen is reduced). In organic compounds, such as butane or ethanol, the loss of hydrogen implies oxidation of the molecule from which it is lost (and the hydrogen is reduced).
In Ethiopian Orthodoxy, fasting (tsome) lasts for 55 continuous days before Easter (Fasika), although the fast is divided into three separate periods: Tsome Hirkal, eight days commemorating an early Christian figure; Tsome Arba, forty days of Lent; and Tsome Himamat, seven days commemorating Holy Week.
It's that time again! Lent begins on March 5 (Ash Wednesday). It's an approximately six-week period in which Christians give up something, usually rich food, to show penitence for the death of Jesus and to emulate his example. Some non-Christians take part just to see how long they can go without their favourite things.