orthoclase
noun
or·tho·clase ˈȯr-thə-ˌklās 
-ˌklāz
: a monoclinic mineral of the feldspar group consisting of a silicate of potassium and aluminum
Word History
Etymology
German Orthoklas, from orth- + Greek klasis breaking, from klan to break — more at clast
First Known Use
1849, in the meaning defined above
- Parapsida
- parapsidal
- parapsidal furrow
- parapsides
- parapsis
- parapsychic
- parapsychical
- parapsychological
- parapsychologies
- parapsychologist
- parapsychologists
- parapsychology
- paraptera
- parapteron
- parapterons
- parapterum
- paraquadrate
- paraquadrates
- paraquat
- paraquats
- paraquets
- pararammelsbergite
- Pararctalian
- parareka
- pararescue