The Collaborative International Dictionary of English v.0.48:

Gonfalon \Gon"fa*lon\, Gonfanon \Gon"fa*non\, n. [OE. gonfanoun,
   OF. gonfanon, F. gonfalon, the same word as F. confalon, name
   of a religious brotherhood, fr. OHG. gundfano war flag; gund
   war (used in comp., and akin to AS. g[=u][eth]) + fano cloth,
   flag; akin to E. vane; cf. AS. g[=u][eth]fana. See Vane,
   and cf. Confalon.]
   1. The ensign or standard in use by certain princes or
      states, such as the medi[ae]val republics of Italy, and in
      more recent times by the pope.
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   2. A name popularly given to any flag which hangs from a
      crosspiece or frame instead of from the staff or the mast
      itself.
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            Standards and gonfalons, 'twixt van and rear,
            Stream in the air.                    --Milton.
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