BOTANIC MATERIA MEDICA, 455 
overlapping those of the leaf opposite to it, 
as the petals of some roses, 
Octandria—ok-tan’-dri-a (Gr. okto, eight, and 
aner, a male; genative, azdros). A class of 
plants having eight stamens, with hermaph- 
rodite flowers. 
Officinal—of-fis’-i-nal (Italian officinale, Fr. of- 
ficina, sold in the shops, from the Lat off- 
cima, a shop where goods are sold). A recog- 
nized medical drug; one used and directed to 
be used by the standard work on medicine. 
Example; the Pharmacopceia, now called Of- 
ficial, ‘ 
Olibanum—o-lib’-a-num (Arabic o/ or al, the 
and /uban, frankincense; Gr. /adanos, the 
frankincense tree). A gum resin of aromatic 
odor and bitter taste; frankincense. 
_ Operculated—o-per’-ku-la’-ted, also Opercu- 
late (Lat. operculum, a lid or cover, from 
operto, | cover over). Any capsule of a fruit 
or seed having a lid or cover, oropening bya 
cap or lid, 
Opium—o’-pi-um (Lat. opium; Gr. opion). The 
juice of the poppy; the concreted juice; a 
medicine and poisonous. 
Opopanax—o-pop’-a-nakx (Gr. ofos, juice, and 
panax, a plant, all heal). A gum resin; the 
dried juice of a plant found in the sub-tropics. 
Orange—(Italian arancio; Spanish naranja, an 
orange, and said to be derived from the Ar. 
naranjt, orange). Socalled from the color 
of the fruit. 
Orchid—or’-kid, Or'chis Lat. orchis; Gr. orchis, 
a plant with roots in form of testicles; Ital. 
orchide, Fr. orchis). Plants with round, fleshy 
