Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
1. sambūcus, i, m. [sambuca], he who plays on the sambuca, Mart. Cap. 9, § 924.
2. sambūcus (săbūcus, ap. Ser. Samm.), i, f., an elder-tree, Plin. 16, 18, 30, § 74; 17, 20, 34, § 151 al.; Ser. Samm. 7, 100; 19, 337; 27, 503 al.
Hence, sambū-cum, i, n., the fruit of the elder, elder-berries, Scrib. Comp. 160.