dif·fer·ence 
/ˈdɪfrəns/ noun
plural dif·fer·encenc·es /ˈdɪfrəns/ noun 1 : the quality that makes one person or thing unlike another [noncount] ▪ She knows the difference between right and wrong. ▪ There's no difference between the two houses. They look exactly the same. [singular] ▪ There's a striking difference in the sisters' looks. [=they look very different from each other] ◊To tell the difference between two people or things is to see how they are unlike each other.
▪ It's hard to tell the difference [=distinguish] between one action movie and another. ▪ The new version is supposed to be much better than the old one, but I can't tell the difference (between them). 2 [count] : something that people do not agree about : a disagreement in opinion
▪ They've always had their differences. [=they have always disagreed about some things] ▪ The debate gave them a chance to air their differences. [=to discuss the things that they disagree about] ▪ We need to find a way to resolve/settle our differences. [=to stop disagreeing, arguing, etc.] ▪ There seems to be a difference of opinion [=people disagree] about what we should do next. ▪ They divorced because of irreconcilable differences. [=serious disagreements that they were not able to settle] 3 [count] : the degree or amount by which things differ
▪ There's a big difference in price. ▪ There's a 15-year age difference between her oldest and youngest children. [=her oldest child is fifteen years older than her youngest child]
▪ It's hard to tell the difference [=distinguish] between one action movie and another. ▪ The new version is supposed to be much better than the old one, but I can't tell the difference (between them).
▪ They've always had their differences. [=they have always disagreed about some things] ▪ The debate gave them a chance to air their differences. [=to discuss the things that they disagree about] ▪ We need to find a way to resolve/settle our differences. [=to stop disagreeing, arguing, etc.] ▪ There seems to be a difference of opinion [=people disagree] about what we should do next. ▪ They divorced because of irreconcilable differences. [=serious disagreements that they were not able to settle]
▪ There's a big difference in price. ▪ There's a 15-year age difference between her oldest and youngest children. [=her oldest child is fifteen years older than her youngest child]
make a difference 1 : to cause a change : to be important in some way
▪ Cost can make a difference in deciding on a college. ▪ “When would you like to leave?” “It makes no difference (to me).” [=it doesn't matter to me; I don't care] ▪ The weather didn't make any difference in our plans. [=didn't change our plans] ▪ It would make a lot of difference if you came. ▪ Your help made a big difference. ▪ It makes very little difference. [=it matters very little] ▪ The size of the engine can make all the difference. [=can be very important; can matter most] ▪ It may not matter to you, but it makes all the difference in the world to me. = It makes a world of difference to me. [=it matters very much to me] 2 : to do something that is important : to do something that helps people or makes the world a better place
▪ She says that she got into politics because she wanted to make a difference.
▪ Cost can make a difference in deciding on a college. ▪ “When would you like to leave?” “It makes no difference (to me).” [=it doesn't matter to me; I don't care] ▪ The weather didn't make any difference in our plans. [=didn't change our plans] ▪ It would make a lot of difference if you came. ▪ Your help made a big difference. ▪ It makes very little difference. [=it matters very little] ▪ The size of the engine can make all the difference. [=can be very important; can matter most] ▪ It may not matter to you, but it makes all the difference in the world to me. = It makes a world of difference to me. [=it matters very much to me]
▪ She says that she got into politics because she wanted to make a difference.
same difference
chiefly US, informal — used to say that two things are not really different in any important way ▪ “They lost 100 games last year.” “Actually, they only lost 96 games.” “Same difference. The point is, they were awful.”
split the difference — see 1split
what's the difference? 1 — used to ask how one thing is different from another ▪ “I like this one a lot more than that one.” “Why? What's the difference (between them)?” 2 or what difference does it/that make? — used to ask why something is important or to suggest that something is not important ▪ What's the difference whether I go or not? ▪ What difference does it make [=what does it matter] if I go with you?
