A reserve or substitute.
reinforcements
A copy of a file or record, stored separately from the original, that can be used to recover the original if it is destroyed or damaged.
An accumulation of material caused by a (partial) obstruction or (complete) blockage of the flow or movement of the material, or an accumulation of material that causes an overflow due to the flow being greater than the maximum possible flow.
Supporting, reinforcing; (music) of or related to accompaniment
Standby, reserve or extra.
That is intended as a backup.
One who occupies a subordinate or auxiliary place; a delegate deputy.
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.
The defensive backs.
An inductive coil or loop that is magnetically powered by a primary in a transformer or similar.
Any flight feather attached to the ulna (forearm) of a bird.
A satellite.
An act of issuing more stock by an already publicly traded corporation.
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.
A secondary circle.
A secondary school.
Anything secondary or of lesser importance.
Produced by alteration or deposition subsequent to the formation of the original rock mass.
Derived from a parent compound by replacement of two atoms of hydrogen by organic radicals
Developed by pressure or other causes.
Dependent or consequent upon another disease, or occurring in the second stage of a disease.
Related to secondary education, i.e. schooling between the ages of (approximately) 11 and 18.
Of less than primary importance.
Originating from a deputy or delegated person or body
Representing a reversion to an ancestral state.
Formed by mixing primary colors.
Next in order to the first or primary; of second place in origin, rank, etc.
Pertaining to the second joint of the wing of a bird.
Relating to the manufacture of goods from raw materials.