Fast

 
Broadly speaking to fast means to willingly abstain from eating, drinking, or both, for a period of time as for religious or medical reason. I could never understand how, in the historical novels I read, people used to eat on a church 'fasting day'. However, it seems that there are various interpretations of fasting and on official fasting days people were allowed one main meal in the 24 hours. 'Days of abstinence' were those on which the eating of meat was forbidden by the Church.

Although this was the primary meaning of fast that I wanted to explore there are, of course, many other meanings including the following:-
1. acting or moving or capable of acting or moving quickly; "The Ferrari is a fast car." "he ran as fast as he could."
2 (used of timepieces) indicating a time ahead of or later than the correct time; "My watch is fast."
3. at a rapid tempo; "The band played a fast fox trot."
4. (of surfaces) conducive to rapid speeds; "Grass tennis courts are faster than clay."
5. resistant to destruction or fading; "My shirt is colour fast."
6. debauched: unrestrained by convention or morality; "She was politelybdewscribed as a fast woman."
7. flying: hurried and brief; "He paid a flying visit."
8. securely fixed in place; "The post was still stuck fast despite being hit by the car."
9.unwavering in devotion to friend or vow or cause; "Theirs was a fast friendship."
10. firmly or closely; "He held fast to the rope."
11. (of a photographic lens or emulsion) causing a shortening of exposure time; "It's a fast lens so you can use 1/125 of a second."