1) Any of the RNA- and protein-rich cytoplasmic organelles that are sites of protein synthesis.

2) Small cellular components composed of specialized ribosomal RNA and protein; site of protein synthesis.

3) A ribosome is a cellular particle made of RNA and protein that serves as the site for protein synthesis in the cell. The ribosome reads the sequence of the messenger RNA (mRNA) and, using the genetic code, translates the sequence of RNA bases into a sequence of amino acids.