The word for today is…
auxiliary (adj) – 1. Giving assistance or support; helping.
2. Acting as a subsidiary; supplementary.
3. Held in or used as a reserve: auxiliary troops.
4. (Nautical) Equipped with a motor as well as sails.
5. (Grammar) Of, relating to, or being an auxiliary verb.
(noun) – 1. An individual or group that assists or functions in a supporting capacity.
2. A member of a foreign body of troops serving a country in war.
3. (Grammar) An auxiliary verb.
4. (Nautical)
(a) A sailing vessel equipped with a motor.
(b) A vessel, such as a supply ship or a tug, that is designed for and used in instances and services other than combat.
Source : The Free Dictionary
Etymology : Auxiliary is used in a wide range of capacities in English to describe a person or thing that assists another. A fire department may bring in auxiliary units, for example, to battle a tough blaze, or a sailboat may be equipped with auxiliary engines to supply propulsion when the wind disappears. In grammar, an auxiliary verb assists another (main) verb to express person, number, mood, or tense, such as have in “They have been informed.” The Latin source of auxiliary is auxilium, meaning “help.”
