Noah Webster
Stability
STABILITY, noun [Latin See Stab.]
1. Steadiness; stableness; firmness; strength to stand without being moved or overthrown; as the stability of a throne; the stability of a constitution of government.
2. Steadiness or firmness of character; firmness of resolution or purpose; the qualities opposite to fickleness, irresolution or inconstancy. We say, a man of little stability or of unusual stability
3. Fixedness; as opposed to fluidity. [I believe not now used.]
Since fluidness and stability are contrary qualities--