(ornithology) Any flight feather attached to the ulna (forearm) of a bird.

Next in order to the first or primary; of second place in origin, rank, etc. / Originating from a deputy or delegated person or body

plural of secondary

The state of being secondary.

(chemistry) in a coordination compound, the number of ions or molecules that are coordinated to the central metal ion; its coordination number

(biochemistry) The general three-dimensional structure of a biopolymer such as DNA or a protein.

(chemistry) An amine containing two radicals, of general formula R₁R₂-NH; the radicals may be the same, different, or part of a ring.

Research performed through the summary, collation or synthesis of the results of existing research.

(British spelling) Any of three colours derived from mixing two primary colours

(finance) The financial market for trading of securities that have already been issued in an initial private or public offering.