A portion of material selected from a larger quantity of material. The term needs to be qualified, e.g. @B00756@, @R05303@, @P04841@, bulked sample, @T06285@. The term 'sample' implies the existence of a @S05463@, i.e. the results obtained on the portions taken are only estimates of the concentration of a @C01281@ or the quantity of a property present in the parent material. If there is no or negligible @S05463@, the portion removed is a @T06284@, aliquot or specimen. The term 'specimen' is used to denote a portion taken under conditions such that the sampling variability cannot be assessed (usually because the population is changing), and is assumed, for convenience, to be zero. The manner of selection of the sample should be prescribed in a sampling plan.