[n] a block of material used in construction work [n] a single undivided natural entity occurring in the composition of something else; "units of nucleic acids"
unit
air, atom, atomic particles, atoms, brute matter, chemical element, component, constituent, core, distillate, distillation, earth, element, elementary particle, elementary unit, elixir, essence, fabric, fire, fundamental particle, gist, heart, hyle, hypos