The translatome is composed of all mRNA fragments that are translated in a moment or condition in a single cell. Usually, the ribosome profiling technique is used to acquire the translatome information.
Unlike the transcriptome, the translatome is a more accurate approximation for estimating the expression level of some genes, since the correlation between the proteome and translatome is higher than the correlation between the transcriptome and proteome. [1].
References
Translatome Wikipedia(Text) CC BY-SA