Has there ever been one issue that has caused trouble between you and another person ? If so , you and the other person have a bone of contention . A bone of contention is the cause of a long-standing argument . The website Dictionary.com says this expression was first used in the early 1700s . This expression comes from the fact that two dogs would often fight over a bone , with neither animal wanting to give in to the other . Today , anything can become a bone of contention between two or more people . A legal document such as a father's will could be a bone of contention between members of his family . Political or religious differences , past mistakes or misunderstandings all make for great bones of contention . Now , another expression related to bone of contention that also uses the word “bone ,” is to have a bone to pick . Let's say you have a problem with someone and you want to resolve it . You could say to them , “Look , I have a bone to pick with you .” This expression refers to a dog chewing endlessly on a bone . It picks it clean . So , a "bone to pick " is a subject or issue that may take much discussion to resolve . “Bone to pick ” is very common and informal . "Bone of contention " is also common but can sound a little formal . A more informal way to say "bone of contention " is sticking point . This is a problem or issue that you can't move beyond . It stops all progress . A sticking point is similar to holding a grudge . When you hold a grudge you keep bad feeling toward someone who has done something bad to you in the past . Two people can also hold a grudge against each other . You might also hear that someone bears a grudge . But holding one is much more common . This is a little different from having a bone of contention . With holding a grudge , we mean a person is holding on to something from the past and it is causing trouble . With a bone of contention , it is the issue that is causing the problem . Now , a more expressive , yet less common , phrase is apple of discord . An apple of discord is an object or issue that can cause anger , arguments and even rivalry between people . This expression comes from Greek mythology . The ancient myth goes something like this : Once there was a great ceremony to celebrate the marriage of Peleus and Thetis . All the important gods and mortals were invited . However , Eris , the goddess of discord and unrest , was not . She really shouldn't have been surprised . I mean , really . Who would want to invite the goddess of discord to their wedding ? Well , to cause trouble , Eris threw a golden apple into the crowd . Written into the apple were the words "the fairest ," “or most attractive ” or something like that . Now , who wouldn't want to catch that ? Well , it turns out that three other Greek goddesses wanted that golden apple . Aphrodite , Athena and Hera all claimed it should be for them . Zeus , the King of the gods , stepped in to resolve the disagreement . He ruled that Paris , a Trojan prince , would act as judge . The three goddesses all tried to influence Paris , which led to a series of terrible events . Very simply stated , the apple caused so many arguments that it eventually led to the Trojan War . Speaking of weddings , here in the United States , there is a tradition at some . Immediately after the ceremony , the unmarried women gather closely in a group . The just-married bride then turns her back to the them and throws her bouquet of flowers up into the air . It is not a competition for the fairest or most beautiful woman to catch . But tradition says that whoever catches the flowers will be the next one to marry . So , it can sometimes lead to a big fight for the bouquet . Do you have any phrases in your language that mean "bone of contention "?