(music) A genre of rock music that is normally published on independent labels, comprising of many different subgenres, mostly distinguished by the prevalence of thick and distorted guitar music.

Energy derived from any source other than fossil fuels. / Energy derived from any renewable source, i.e other than fossil fuels or nuclear fission.

(US) Alternative spelling of alternative energy

plural of alternative lifestyle

(physics, cosmology) A hypothetical world situated in a different dimension of space and time than the real world consisting of the universe known and experienced by human beings.

Alternative form of alternate universe

(statistics) A rival hypothesis to the null hypothesis. Their likelihoods are compared by a statistical hypothesis test.

Counterfactual history, a form of scientific speculation used by historians.

(topology) A knot that has a knot diagram in which, in traveling along the knot, one passes through intersections alternatingly: over, under, over, under, etc.

(biology) Each of the two forms of an organism whose life cycle involves alternation of generations, or the fact of such alternation occurring in a given organism.