Hypothetical compounds having the structure $\ce{RC(NH2)3}$, and N-substituted derivatives thereof. $\ce{(R2N)4C}$ are generically included, but such use is obsolescent.
Source: PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1354 [Terms] [Paper]