Gudgeon and New kid on block

Gudgeon noun - Small spiny-finned fish of coastal or brackish waters having a large head and elongated tapering body having the ventral fins modified as a sucker.

New kid on block and gudgeon are semantically related. In some cases you can use "New kid on block" instead a noun "Gudgeon".

Gudgeon and new kid on block are semantically related. Sometimes you can use "Gudgeon" instead a noun phrase "New kid on block".