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Webster 1913 Edition
Ladanum
Lad′a-num
,Noun.
 [L. 
ladanum
, ledanum
, Gr. λάδανον
, λήδανον
, fr. λῆδον 
name of a shrub, mastic; cf. Per. lādan
, lāden
. Cf. Laudanum
.] A gum resin gathered from certain Oriental species of 
Cistus
. It has a pungent odor and is chiefly used in making plasters, and for fumigation. [Written also 
labdanum
.] Webster 1828 Edition
Ladanum
LAD'ANUM
,Noun.