The largest ribonucleoprotein component of RIBOSOMES. It contains the domains which catalyze formation of the peptide bond and translocation of the ribosome along the MESSENGER RNA during GENETIC TRANSLATION.

Synonyms: Ribosomal Subunits, Large Subunits, Large Ribosomal Large Ribosomal Subunits Subunit, Large Ribosomal Large Ribosome Subunit Ribosome Subunit, Large Subunits, Large Ribosome Large Ribosomal Subunit Large Ribosome Subunits Subunit, Large Ribosome Ribosome Subunits, Large Ribosomal Subunit, Large