Tributary \Trib"u*ta*ry\, n.; pl. {Tributaries}.
1. A ruler or state that pays tribute, or a stated sum, to a
conquering power, for the purpose of securing peace and
protection, or as an acknowledgment of submission, or for
the purchase of security.
[1913 Webster]
2. A stream or river flowing into a larger river or into a
lake; an affluent.
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