size-exclusion chromatography (SEC) - same as steric exclusion chromatography.

slurry packing - the technique most often used to pack HPLC columns with microparticles. The packing is suspended in a slurry (10% wt/vol) and is rapidly pumped into the empty column. Special high-pressure pumps are used.

solid phase extraction (SPE) - A sample-preparation technique that uses a solid-phase packing contained in a small plastic cartridge. The solid stationary phases are the same as HPLC packings; however, the principle is the same as in frontal chromatography. The process as most often practiced requires four steps: conditioning the sorbent, adding the sample, washing away the impurities, and eluting the sample in as small a volume as possible with a strong solvent.

solvent strength - refers to the ability of a solvent to elute a particular analyte or compound from a column. Described by Lloyd Snyder for LEAC (LSC) adsorption chromatography on alumina solvents were quantitatively rated in an elutropic series. No elutropic series exists for other modes.