(general scholarship and historiography) A selection, distillation, summary or compilation of primary sources, secondary sources, or both.

(British spelling) Any colour that results from the mixing of two secondary colours, or of a primary colour and an adjacent secondary colour.

(economics) An industry that provides goods or services to consumers using raw materials from primary industry and goods processed by secondary industry.

plural of tertiary industry

plural of tertiary sector

(economics) The sector of the economy that principally provides goods and services to consumers using goods produced by the other sectors.

Alternative spelling of tertiary colour

higher education

plural of tertiary source

plural of tertiary phosphine