Definition
Ordered blue field
A nontrivial ordered blueprint whose nonzero monomials are all units.
Definition
An ordered blue field is a nontrivial ordered blueprint such that
that is, every nonzero element of its underlying multiplicative monoid is invertible.
Scope
The term concerns the monomial skeleton . It does not assert that the ambient semiring is a field, nor does it by itself supply additive inverses or unique weak inverses.
Fields, partial fields, and hyperfields have ordered-blue-field avatars after their additive data are encoded in the order. General ordered blue fields form a larger class. Additional conditions define idylls and pastures.
References
Matthew Baker and Oliver Lorscheid, The moduli space of matroids, §§2.6 and 6.4.