say it: kahn-suhn-TRAY-shuhn
concentration is a noun meaning "the strength of a solution; number of molecules of a substance in a given volume". It carries 7 recorded senses.
strengthening the concentration (as of a solute in a mixture) by removing diluting material
increase in density
complete attention; intense mental effort
bringing together military forces
great and constant diligence and attention
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for concentration come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.