Technical name for "many-to-many" mappings

Question

A one-to-one mapping is a bijection. A many-to-one mapping is a "general function" and might also be a "surjective function".

Is there a similarly technical name for a many-to-many mapping, or should I just write "many-to-many" whenever describing such a thing. Same question for a "one-to-many" mapping (perhaps "inverse general function")?

EDIT: For what I mean by a "many-to-many" mapping:

Set 1: A, B, C, D
Set 2: W, X, Y, Z

A maps to W
B maps to W and X
C and D map to Y and Z (many-to-many relationship)

In this case, multivalued is probably the right term, as janmarqz suggests. — Cameron Williams, Jan 14 '14 at 03:13

score 10 · Accepted Answer · edited Jan 14 '14 at 08:54

10

Another common name is relation.

edited Jan 14 '14 at 08:54

jmc

225
2
11

answered Jan 14 '14 at 03:35

rschwieb

153,510

Thanks! Can you double check your link? I think you had a little copy-paste mishap. – Kevin Jan 14 '14 at 04:14
@Kevin thanks! Yes, I was trying to cut and paste on a tablet and I'm not very good at it. – rschwieb Jan 14 '14 at 12:02

score 3 · Answer 2 · answered Jan 14 '14 at 03:10

3

Multivalued function is used. In places like this you can see more details and many other technical situations.

answered Jan 14 '14 at 03:10

janmarqz

10,538

Technical name for "many-to-many" mappings

2 Answers2