The Jargon File (version 4.4.7, 29 Dec 2003):

Yu-Shiang Whole Fish
 /yoo?shyang hohl fish/, n. obs.

    The character gamma (extended SAIL ASCII 0001001), which with a loop in its
    tail looks like a little fish swimming down the page. The term is actually
    the name of a Chinese dish in which a fish is cooked whole (not parsed)
    and covered with Yu-Shiang (or Yu-Hsiang, or in modern Pinyin
    transliteration yuxiang) sauce. Usage: primarily by people on the MIT LISP
    Machine, which could display this character on the screen. Tends to elicit
    incredulity from people who hear about it second-hand.

    Yu Shiang Whole Fish is alive and well in Unicode as U+0263 LATIN SMALL
    LETTER GAMMA (as opposed to the actual Greek letter at U+03B3, which
    usually has a loopless glyph; the form of U+0263 is consistently loopy).
    This symbol is included in Unicode as a Latin letter because it is used in
    the International Phonetic Alphabet. In the IPA, gamma represents a voiced
    velar fricative, the sound commonly transcribed ?gh? in Arabic or Klingon.

    Z


The Free On-line Dictionary of Computing (30 December 2018):

Yu-Shiang Whole Fish

   /yoo-shyang hohl fish/ An obsolete name for the Greek
   character gamma (extended SAIL ASCII code 9, Unicode glyph
   0x0263) which with a loop in its tail looks like a little fish
   swimming down the page.  The term is actually the name of a
   Chinese dish in which a fish is cooked whole (not parsed)
   and covered with Yu-Shiang (or Yu-Hsiang) sauce.  Used
   primarily by people on the MIT LISP Machine, which could
   display this character on the screen.  Tends to elicit
   incredulity from people who hear about it second-hand.

   [Jargon File]

   (1995-01-31)