The megalative degree is the second-
order form of the superlative and is applied to the inflexional form of an adjective or adverb as the superlative would be. It is formed by cascading a superlative forming determiner (such as 'most') with the compound superlative form of an adjective (such as 'happiest'). Alternatively it
may be formed by appending a superlative forming suffix (such as '-
est') to an adjective that is already declined in the superlative degree.
Whilst often regarded as grammatically incorrect, the megalative degree is commonly used when comparing a
number of things to express a higher degree of the
quality or attribute in a simple word than the superlative would alone.
"That's the most happiest I've ever seen him."
(the phrase 'most happiest' is a compound megalative)
"She gave the
bestest brain I've ever had."
(the word '
bestest' is declined in the megalative degree)