The Superlative Degree of the adjective does not really state that a quality is present to an extreme degree; rather, it compares three or more entities in terms of a quality. Consequently, you can easily say "He is the smartest student in the class, but she is really smarter", indicating the "she" is not in the class and that the class in general does not show a high degree of intelligence. When the comparison is particluar (that is when one entity is explicitly compared with two or more entities) we usually use "-est" or "most" in English. (Remember: you use the comparative degree to compare one entity with one entity.) Thus, you can say, "Henry is the smartest elephant in the circus." Or, "Elephants are the most unforgetting of animals." In the first example, the "smartness" of Henry is compared with all other individual elephants; in the second, the entity is the collectivity of elephants which is compared with all other such collectivities.
In Latin, the superlative degree is used for such particular comparisons, but it may also imply a comparison, not with two or more specific entities, but with a group which, as a whole, is divided into more than two or more groups. You can visualize this by recalling how the Comparative Degree can compare one entity with the norm or standard: _________|_smarter_____. The Superlative Degree works similarly: _________|_________|_very smart__. As this indicates, you translate such superlatives with "very." Other translations are also available: for example, "really smart." NOTE: this is not "smarter than average" (that would be the comparative, "pretty smart"), this is "way smart" or "outstandingly smart", etc.