south·ing /ˈsaʊθɪŋ, ðɪŋ/
 南向,南進,南行航程
 South v. i. [imp. & p. p. Southed p. pr. & vb. n. Southing.]
 1. To turn or move toward the south; to veer toward the south.
 2. Astron. To come to the meridian; to cross the north and south line; -- said chiefly of the moon; as, the moon souths at nine.
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 South·ing n.
 1. Tendency or progress southward; as, the southing of the sun.
 2. The time at which the moon, or other heavenly body, passes the meridian of a place.
 3. Astron. Distance of any heavenly body south of the equator; south declination; south latitude.
 4. Surv. & Navigation Distance southward from any point departure or of reckoning, measured on a meridian; -- opposed to northing.
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