The definition of appreciable is something that is big enough to be seen and to be a significant amount.(adjective)
To add an extra cup of sugar to a cake mix would change both the flavor and texture so that would be an example of an appreciable amount of sugar.
See appreciable in Webster's New World College Dictionary
Origin: ME & OFr < ML appretiabilis: see appreciate & -able
See appreciable in American Heritage Dictionary 4
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