The hoof or foot of the beast. a cloven hoof (hoof is split example A Camel has a cloven hoof) this makes it unclean . while a hoof without a split is not unclean. Example Cows horses buffalo ect So... A horse is unclean but they still took it onto the ark. however a dog or a cow is clean.
The Bible lists requirements on clean and unclean animals. God says that one must not eat unclean animals, for it is a sin. To be clean an animal must have split hooves and chew its cud. This means a cow is clean, but a jaguar is not. For aquatic animals, the animal must have scales, fins, and gills. This means shellfish are unclean animals, but tuna is clean. Jews follow kosher laws which are the laws on clean and unclean animals.
A clean animal is a healthy animal, and an unclean animal is an unhealthy one. To see this one must open his eyes because his mind is small.
Another thought:
The meaning has changed a bit over the years.
Initially, when God created Adam and Eve, ALL creatures, including man, ate only vegetation(Genesis 1:29-30). Many years after Adam's sin, when Noah went into the ark, he was told to take 'seven clean animals' and 'two unclean' from each group(Genesis 7:2,3,8,9) because of what was acceptable to God as a sacrifice(Genesis 8:20), which was now needed because of Adam's sin.
When Noah came OUT of the ark, God gave permission for the eating of meat, and ALL animals were acceptable as food(Genesis 9:3+4). Centuries later, however, God gave the Israelites the Mosaic Law, including dietary laws,which gave details as to clean and unclean animals, for EATING(Leviticus 11:3)(Deuteronomy 14:3-6)(Leviticus 11:4-8, 26, 27; Deuteronomy 14:7, 8) for health reasons(Leviticus 11:46, 47). The Israelites wandered for MANY years in the wilderness, basically camping in the heat, so cleanliness was vital for health. It is felt by many that cud-chewing animals, without claws, are often cleaner in their own eating habits, and their complex digestive process removes impurities better, making them safer for humans to eat. God would, of course, know this, even if people did not. The Mosaic Law ended with the death of Jesus, so the law on clean and unclean animals ended with it (Acts 10:9-16; Ephesians 2:15).
It is unclear exactly what purpose the unclean animals served. Perhaps they were there to increase the beauty of the planet or perhaps so that there would be a test for those who wanted to follow the law. The Bible does not make explicit what the reason is for unclean animals to exist.
Lev:11:47: To make a difference between the unclean and the clean, and between the beast that may be eaten and the beast that may not be eaten.
The unclean animals.
Noah took clean and unclean animals because God told him to, and Noah had strong faith in God(Genesis 6:9 + 7:2). Noah used the 'clean' animals for the purpose of sacrifice to God(Genesis 8:20) (Leviticus 1:10)(Leviticus 1:14)(Leviticus 17:11)
Animals get bacteria due to their diet, their habits, and unclean food resources.
In Judaism, cleanliness has nothing to do with it. These animals are unkosher. They are not "unclean." Unkosher animals are animals that are not fit to use as a food animal.
Gentiles
In various religious contexts, unclean animals are those that are considered impure or unfit for consumption based on religious laws or beliefs. These animals may include pigs, shellfish, and certain birds, among others. The classification of unclean animals varies among different religions and cultures.
it kills the animals and make the water unclean
Pig was one of the animals considererd unclean.
Dogs in the Bible were unclean animals. I am no dream interpreter, but maybe it means something about getting rid of unclean things in your life?
Just because certain animals were unfit for human consumption did not mean that those animals did not deserve to live.
an unclean environment causes pollution that eats away the earths ozone layer causing animals to be extincted; such as polar bears as the ice caps are melting. by cayman Lambert
If you are referring to the "food law" that is described in the bible for Christianity, then any animal that has a "hoof" is considered to be unclean. For example: pigs, cows, or deer. Hope this helped :)