Imines bearing a hydrocarbyl group on the nitrogen atom R2C=NR' (R' ≠ H). Considered by many to be synonymous with azomethines.
Source: PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1364 [Terms] [Paper]