relation

n 1: an abstraction belonging to or characteristic of two

entities or parts together

2: the act of sexual procreation between a man and a woman; the

man's penis is inserted into the woman's vagina and

excited until orgasm and ejaculation occur [syn: {sexual

intercourse}, {intercourse}, {sex act}, {copulation}, {coitus},

{coition}, {sexual congress}, {congress}, {sexual

relation}, {carnal knowledge}]

3: a person related by blood or marriage; "police are searching

for relatives of the deceased"; "he has distant relations

back in New Jersey" [syn: {relative}]

4: an act of narration; "he was the hero according to his own

relation"; "his endless recounting of the incident

eventually became unbearable" [syn: {telling}, {recounting}]

5: (usually plural) mutual dealings or connections among

persons or groups: "international relations"

relation

1. A subset of the {product} of two sets, R : A

x B. If (a, b) is an element of R then we write a R b,

meaning a is related to b by R. A relation may be:

{reflexive} (a R a), {symmetric} (a R b ◦> b R a),

{transitive} (a R b & b R c ◦> a R c), {antisymmetric} (a R b

& b R a ◦> a ◦ b) or {total} (a R b or b R a).

See {equivalence relation}, {partial ordering}, {pre-order},

{total ordering}.

2. A {table} in a {relational database}.

(1995-02-28)