What is "at call"

Call \Call\, n.

1. The act of calling; -- usually with the voice, but often otherwise, as by signs, the sound of some instrument, or by writing; a summons; an entreaty; an invitation; as, a call for help; the bugle's call. ``Call of the trumpet.''
   --Shak.

   I rose as at thy call, but found thee not.
   --Milton.

2. A signal, as on a drum, bugle, trumpet, or pipe, to summon soldiers or sailors to duty.

3. (Eccl.) An invitation to take charge of or serve a church as its pastor.

4. A requirement or appeal arising from the circumstances of the case; a moral requirement or appeal.

   Dependence is a perpetual call upon humanity.
   --Addison.

   Running into danger without any call of duty.
   --Macaulay.

5. A divine vocation or summons.

   St. Paul himself believed he did well, and that he had a call to it, when he persecuted the Christians.
   --Locke.

6. Vocation; employment.

   Note: [In this sense, calling is generally used.]

7. A short visit; as, to make a call on a neighbor; also, the daily coming of a tradesman to solicit orders.

   The baker's punctual call.
   --Cowper.

8. (Hunting) A note blown on the horn to encourage the hounds.

9. (Naut.) A whistle or pipe, used by the boatswain and his mate, to summon the sailors to duty.

10. (Fowling) The cry of a bird; also a noise or cry in imitation of a bird; or a pipe to call birds by imitating their note or cry.

11. (Amer. Land Law) A reference to, or statement of, an object, course, distance, or other matter of description in a survey or grant requiring or calling for a corresponding object, etc., on the land.

12. The privilege to demand the delivery of stock, grain, or any commodity, at a fixed, price, at or within a certain time agreed on. [Brokers' Cant]

13. See Assessment, 4. At call, or On call, liable to be demanded at any moment without previous notice; as money on deposit. Call bird, a bird taught to allure others into a snare. Call boy

    1. A boy who calls the actors in a theater; a boy who transmits the orders of the captain of a vessel to the engineer, helmsman, etc.

    2. A waiting boy who answers a cal, or cames at the ringing of a bell; a bell boy.

       Call note, the note naturally used by the male bird to call the female. It is artificially applied by birdcatchers as a decoy.
       --Latham.

       Call of the house (Legislative Bodies), a calling over the names of members, to discover who is absent, or for other purposes; a calling of names with a view to obtaining the ayes and noes from the persons named.

       Call to the bar, admission to practice in the courts.

prep.phr. (context obsolete English) available when requested