"a reserve supply of food"; "a spare tire"; "spare parts"
"a bare livelihood"; "a scanty harvest"; "a spare diet"
"trying to lose excess weight"; "found some extra change lying on the dresser"; "yet another book on heraldry might be thought redundant"; "skills made redundant by technological advance"; "sleeping in the spare room"; "supernumerary ornamentation"; "it was supererogatory of her to gloat"; "delete superfluous (or unnecessary) words"; "extra ribs as well as other supernumerary internal parts"; "surplus cheese distributed to the needy"
"a free hour between classes"; "spare time on my hands"
"a plain hair style"; "unembellished white walls"; "functional architecture featuring stark unornamented concrete"
"the spare figure of a marathon runner"; "a body kept trim by exercise"
"I'll spare you from having to apologize formally"
"he asked if they could spare one of their horses to speed his journey"