Any activity performed by an astronaut outside of a space vehicle in space.

(uncountable) The application of science and engineering to the exploration and utilization of outer space / (countable) Any particular scientific or engineering discipline used in this field

(uncountable) Flight into, from or through space. / (countable) A voyage in space.

(mathematics) A vector space whose basis of real numbers has three vectors

(physics) The quantization of one or more components of the angular momentum of a system

(idiomatic) An indication that a development will follow.

plural of space probe

plural of space alien

(chiefly US) An extraterrestrial being; a visitor from outer space.

plural of space defense