Pronunciation: [d͡ʒˈɪfɪəst] (IPA) 
The correct spelling of the word "jiffiest" is often debated, with variations such as "jiffyest" being used. However, the IPA phonetic transcription sheds some light on the proper spelling: the "ie" sound is represented by the "i" and "e" combination, and "jiffy" ends in a "y" sound. Therefore, the addition of the suffix "-est" simply involves adding the letters "e" and "s" to the end of "jiffy", resulting in "jiffiest."
The term "jiffiest" does not have a specific etymology as it is a derivative of the word "jiffy". The word "jiffy" is believed to have originated from the colloquial English expression "in a jiffy" which dates back to the 18th century. The exact origin or etymology of "jiffy" is uncertain, but it is often used to mean a short, brief, or quick amount of time. "Jiffiest" is formed by adding the suffix "-est" to "jiffy", indicating the superlative form, meaning "the most brief or quickest". However, it is worth noting that "jiffiest" is a relatively uncommon word and is not commonly used in contemporary English.
