skinniest

/S K IH1 N IY0 AH0 S T/
adjective
  1. 1

    Thin, generally in a negative sense (as opposed to slim, which is thin in a positive sense).

    โ€œHer recent weight loss has made her look rather skinny than slenderโ€

  2. 2

    (of food or beverages) Low-fat.

  3. 3

    Naked; nude (chiefly used in the phrase skinny dipping).

  4. 4

    (of clothing) tight-fitting

Source: https://en.wiktionary.org/wiki/skinniest, https://en.wiktionary.org/wiki/skinny