by-form 
(bīfôrm′)
(bīfôrm′)n.
A variant form of a word or morpheme, often one whose formation or development is obscure or unexpected.
- stereoisomeric
- stereoisomerism
- stereolithography
- stereologic
- stereological
- stereologically
- stereologist
- stereology
- stereomicroscope
- stereomicroscopic
- stereomicroscopy
- stereophonic
- stereophonically
- stereophony
- stereopsis
- stereopticon
- stereoscope
- stereoscopic
- stereoscopically
- stereoscopist
- stereoscopy
- stereotactic
- stereotactical
- stereotactically
- stereotactic radiosurgery