No...synthroid does not cause black stools. This could be a sign of gastric (stomach) bleeding, certain foods, or a medication (like Pepto Bismol)... A. Black stools can be a sign of gastrointestinal bleeding (melena)....OR it can be a sign of someone taking Pepto Bismol for their loose bowel...
A person's brother or sister. Classified under: Nouns denoting people. Synonyms: sib; sibling. Hypernyms (sibling is a kind of...): relation; relative (a person related by blood or marriage) Hyponyms (each of the following is a kind of sibling): half blood (one of siblings who have only one parent in common) quad; quadruplet (one of four children born at the same time from the same pregnancy) quin; quint; quintuplet (one of five children born at the same time from the same pregnancy)
A sibling is your brother or sister. It's that simple. The word sibling once meant anyone who is related to you, but now it's reserved for children of the same parent or parents. It is a word that was once out of use but then brought back into English in the early 1900s as a useful word in anthropology. If you and your brother fight all of the time, your parents might call it sibling rivalry. You might just call him annoying and run from the room.