aldehydo-
combining form 
Etymology: International Scientific Vocabulary, from aldehyde + -o- 
1. usually italic : containing the aldehyde group  — in names of open-chain aldehydic forms of specific sugars
< aldehydo-d-galactose >
— compare ald-
2. : formyl 
< aldehydobenzoic acid >
1. usually italic
< aldehydo-d-galactose >
— compare ald-
2.
< aldehydobenzoic acid >