Vigintile

Part of speech: noun, adjective

Definitions

1. A statistical measure that divides a distribution into twenty equal parts, with each part containing five percent of the data
2. A statistical term representing one of the twenty equal divisions of a data set, each encompassing five percent of the total values
3. An analytical concept that segments a population into twenty equal segments, each segment comprising five percent of the overall distribution

Etymology: Vigintile is a plain technical coinage, built on the Latin number "vīgintī" ("twenty") and the adjective-forming suffix "-ilis," which gives English words like "percentile" and "decile" their shape. It is the twenty-part sibling of those terms: where a decile splits data into ten groups, a vigintile splits it into twenty, so each slice holds five percent of the values. The word works as both a noun and an adjective. As a noun it names one of the twenty groups themselves, and as an adjective it describes something belonging to such a division, such as a vigintile boundary or a vigintile rank. Like "decile," it is an arithmetic label that statisticians needed to name a particular partition, rather than a word with a long life in everyday speech.