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While the word is much less common in everyday speech, the word "habilitate" means "to make fit" or "to become suitable for certain conditions". Therefore, to rehabilitate means "to make fit (or suitable) again".
Potable, according to dictionary.com, means "fit or suitable for drinking."
"Accurate" is a suitable word that means proven to be correct.
edible
That is not a word. The actual word would be unsuitable. It means inappropriate.
The word you are looking for is "desalination." It refers to the process of removing salt from seawater or brackish water to make it suitable for drinking or agricultural use.
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The word "mature" could be a suitable option for a word that rhymes with "sober" and means older.
The most suitable antonym for the word cargo is bit. An antonym is a word that means the opposite of a particular word.
The root word for "fitter" is "fit," which means to be suitable, appropriate, or in good physical condition.
'Potable' is usually used as such, referring mainly to water.
The prefix word for suitable is "in-".