prob-, proba-, probat-, prov-

(Latin: upright, good, honest; to try, to test, to examine; to demonstrate)

disprovable (adjective) (not comparable)
Subject to being invalid: The statement Linda made in court was disprovable and discredited by the lawyers and judge.
Act of disproving; disproof.
disprove (verb), disproves; disproved; disproving
To show that an assertion, claim, etc. is false, invalid, or wrong; to refute; to invalidate.
1. One who disproves or confutes.
2. A debater who refutes or disproves by offering contrary evidence or argument; rebutter, refuter, confuter.
1. Resisting the effect of flames.
2. Not readily ignited or burned by flames.
3. Not likely to burn or to be damaged by fire; such as, flameproof clothing.
1. Designed to continue working properly in the face of any kind of human error, incompetence, or misuse.
2. So well thought out that failure is thought to be impossible.
improbability (s) (noun), improbabilities (pl)
1. Not likely to be true or to occur or to have occurred; unlikelihood: The account James told us was so suspicious and unbelievable that the improbability of his story was concluded instead!
2. Something doubtful, dubious, questionable, or unlikely: Catching the flu makes you feel terrible and also makes it a real improbability to laugh or even smile!
improbable (adjective), more improbable, most improbable
1. Unlikely to take place, to be true, or to happen: It is improbable that the temperature will be 30°C. and hot the next day taking into consideration that it is presently -10°C. and snowing heavily at the moment!
3. Too far-fetched to be considered believable: It is really rather improbable that Tom's parents are millionaires considering that they live in a disreputable part of town!
improbably (adverb), more improbably, most improbably
1. Pertaining to something that is not easy to believe: In Toronto Sam finally was able to see the improbably tall CN Tower, rising much higher than any of the other buildings in the downtown area.
2. Concerning something that is unlikely to take place or be true: Dick thought that his invention would conceivably, but improbably, be realized, but he never gave up hope that it would someday come true!
improvable (adjective), more improvable, most improvable
1. Capable of being refined; susceptible to betterment: Mrs. Thompson thought that Jill's handwriting was improvable if she practised more with forming the letters in the words carefully.
2. Capable of being used to advantage; profitable; serviceable; advantageous: The cultivation of the land would be improvable if the watering system was more efficient.
improvably (adverb) (not comparable)
Concerning how something or someone advances to a more desirable, valuable, or excellent state: Neal and Stella could see the workers improvably proceeding with the roof only after a few months of building their new house!

Joan practiced piano improvably from day to day and her parents complimented her on her progress.

improve (verb), improves; improved; improving
1. To raise to a more desirable or more excellent quality or condition; to make better.
2. To increase the productivity or value of land or property.
3. To put to good use; to use profitably.
4. To make beneficial additions or changes.
1. The act or process of improving.
2. The state of being improved.
3. A change or addition that improves.
1. A person or thing that improves.
2. Someone devoted to the promotion of human welfare and to social reforms.
3. A component that is added to something to improve it.
probability (s) (noun), probabilities (pl)
1. The likelihood of something occurring: The probability of the condo having increased in value is assumed since it has been recently renovated.
2. The most plausible or feasible possibility: There is a probability that the coronavirus will continue to affect the economy of the country.
3. A measure of how conceivable it is that some occurrence will take place: The probability of it snowing is about 50%.