Noun
diffeology (plural diffeologies)
(differential geometry) The set of smooth parametrizations of a given set
X
{\displaystyle X}
; the set of smooth maps
S
→
X
{\displaystyle S\rightarrow X}
, where
S
{\displaystyle S}
is any open set
⊆
R
n
{\displaystyle \subseteq \mathbb {R} ^{n}}
; the theory of such constructs.