1. The quality or condition of being unstable; lack of stability, firmness, or steadiness; liability to give way or to fail; insecurity; precariousness; as, the instability of a building. [ 1913 Webster ]

2. Lack of determination of fixedness; inconstancy; fickleness; mutability; changeableness; as, instability of character, temper, custom, etc. Addison.

Syn. -- Inconstancy; fickleness; changeableness; wavering; unsteadiness; unstableness. [ 1913 Webster ]

1. To set in a seat; to give a place to; establish (one) in a place. [ 1913 Webster ]

She installed her guest hospitably by the fireside. Sir W. Scott. [ 1913 Webster ]

2. To place in an office, rank, or order; to invest with any charge by the usual ceremonies; to instate; to induct; as, to install an ordained minister as pastor of a church; to install a college president. [ 1913 Webster ]

Unworthily
Thou wast installed in that high degree. Shak. [ 1913 Webster ]

1. The act of installing; as, the installation of the air conditioner took half an hour.
Syn. -- installing, setting up. [ 1913 Webster +PJC ]

2. Hence: the act of installing (a person) or giving possession of an office, rank, or order, with the usual rites or ceremonies; as, the installation of an ordained minister in a parish. [ 1913 Webster ]

On the election, the bishop gives a mandate for his installation. Ayliffe. [ 1913 Webster ]

3. (Mech.) The whole of a system of machines, apparatus, and accessories, sometimes including the buildings and gorounds on which they are located, when set up and arranged for practical working, as in electric lighting, transmission of power, etc.; as, our installation in Baton Rouge can produce ten thousand gallons a day; we should move our drying installation from building A to building B. [ 1913 Webster +PJC ]

4. (Mil.) The whole of a military base, post, camp, outpost, etc., constructed and operated for support of military operations. [ PJC ]

Take oaths from all kings and magistrates at their installment, to do impartial justice by law. Milton. [ 1913 Webster ]

2. The seat in which one is placed. [ Obs. ] [ 1913 Webster ]

The several chairs of order, look, you scour; . . .
Each fair installment, coat, and several crest
With loyal blazon, evermore be blest. Shak. [ 1913 Webster ]

3. A portion of a debt, or sum of money, which is divided into portions that are made payable at different times; that portion of a debt payed back in any one payment; as, the next installment is due January first. Payment by installment is payment by parts at different times, the amounts and times being often definitely stipulated. Bouvier. [ 1913 Webster +PJC ]

4. a part of a broadcast serial. [ wns=1 ]
Syn. -- episode. [ WordNet 1.5 ]

5. a part of a published serial. [ wns=2 ] [ WordNet 1.5 ]

1. The act or quality of being instant or pressing; urgency; solicitation; application; suggestion; motion. [ 1913 Webster ]

Undertook at her instance to restore them. Sir W. Scott. [ 1913 Webster ]

2. That which is instant or urgent; motive. [ Obs. ] [ 1913 Webster ]

The instances that second marriage move
Are base respects of thrift, but none of love. Shak. [ 1913 Webster ]

3. Occasion; order of occurrence. [ 1913 Webster ]

These seem as if, in the time of Edward I., they were drawn up into the form of a law, in the first instance. Sir M. Hale. [ 1913 Webster ]

4. That which offers itself or is offered as an illustrative case; something cited in proof or exemplification; a case occurring; an example; as, we could find no instance of poisoning in the town within the past year. [ 1913 Webster +PJC ]

Most remarkable instances of suffering. Atterbury. [ 1913 Webster ]

5. A token; a sign; a symptom or indication. Shak. [ 1913 Webster ]

Causes of instance, those which proceed at the solicitation of some party. Hallifax. --
Court of first instance, the court by which a case is first tried. --
For instance, by way of example or illustration; for example. --
Instance Court (Law), the Court of Admiralty acting within its ordinary jurisdiction, as distinguished from its action as a prize court.

Syn. -- Example; case. See Example. [ 1913 Webster ]