reddendum

Red*den"dum (rd*dn"dm), n. Etym: [Neut. of L. reddendus that must be given back or yielded, gerundive of reddere. See Reddition.] (Law) Defn: A clause in a deed by which some new thing is reserved out of what had been granted before; the clause by which rent is reserved in a lease. Cruise.

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