(anatomy) Any of the spaces between the placental villi that contain maternal blood

(mathematics) Any topological subset of Euclidean space that is a compact set

(of text) Formatted so that there is a full blank line between each line of text; the style of formatting required by many entities inside business, academia, and publishing.

(mathematics, physics) A coordinate system (or a frame of reference) defined with respect to the distant stars, whose relative positions do not change over reasonably long periods of time

(letterpress typography) A piece of metal type used to create the narrowest space. / (typography, US) The narrowest space appearing between letters and punctuation.

(mathematics) Either of two spaces between which an isometry exists

A variable width space, or a number of space characters, inserted between words to make a line of printed text a desired length

any of several regions in a glow discharge in which little or no light is produced / (astronomy) the intergalactic void that exists between galaxies

simple past tense and past participle of double-space

(mathematics) A Riemann space in which the contracted curvature tensor is proportional to the metric tensor