There are various synonyms for the word 'tumours' which refer to abnormal growths of cells in the body. Some of the commonly used synonyms include neoplasms, growths, masses, lumps, nodules, and lesions. Neoplasms refer to the abnormal growth of cells and can be benign or malignant. Growths, masses, and lumps also refer to abnormal growths of cells, while nodules are small, solid, and raised growths. Lesions refer to any abnormal or damaged tissue in the body, including tumours. The type of synonym used depends on the context in which it is being used, and the medical condition being referred to.