middle fifty vs midspread

middle fifty and midspread both are nouns.

Word	Noun	Adjective	Verb	Adverb
middle fifty	Yes	No	No	No
midspread	Yes	No	No	No

As nouns, middle fifty and midspread are synonyms defined as:

middle fifty and midspread: a measure of statistical dispersion, being equal to the difference between the upper and lower quartiles.

Other synonyms of middle fifty include interquartile range.

middle fifty (noun)	midspread (noun)
a measure of statistical dispersion, being equal to the difference between the upper and lower quartiles.	a measure of statistical dispersion, being equal to the difference between the upper and lower quartiles.