adj

• (organic chemistry) Derived from a parent compound by replacement of two atoms of hydrogen by organic radicals.
• (geology) Produced by alteration or deposition subsequent to the formation of the original rock mass.
• (geology) Developed by pressure or other causes.
  "secondary cleavage"
• (anatomy) Pertaining to the second joint of the wing of a bird.

noun

• (ornithology) Any flight feather attached to the ulna (forearm) of a bird.
• (aviation) A radar return generated by the response of an aircraft's transponder to an interrogation signal broadcast by a radar installation, containing additional encoded identification and situational data not available from a simple primary return.
• (military) The second stage of a multistage thermonuclear weapon, which generates a fusion explosion when imploded as an indirect result of the fission explosion of the primary, and which, in a few extremely large weapons, itself implodes a fusion tertiary.
• (finance) An act of issuing more stock by an already publicly traded corporation.