HackerVoca

stable : invariable, steadfast, unchangeable, constant, steady
stagger : sway, totter, waver, falter / / verb [intransitive]

1 to become weaker and unable to continue in an effective way: The economy is showing signs of faltering. | My mother's iron grip upon the household never faltered.

2 to speak in a voice that sounds weak and uncertain, and keeps stopping: Laurie's voice faltered as she tried to thank him.

3 to become less certain and determined that you want to do something: We must not falter in our resolve.

4 to move unsteadily because you suddenly feel weak or afraid: She faltered for a moment.

stagnant / / adjective

1 stagnant water or air does not move or flow and often smells bad: a stagnant pond

2 not changing, developing, or making progress; inactive: Industrial output has remained stagnant.

stagnancy noun [uncountable]
stagnantly adverb : inert, inactive