Gudgeon and Tongue

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.

Tongue and gudgeon are semantically related. In some cases you can use "Tongue" instead a noun "Gudgeon".

Tongue noun - The stock of words, pronunciation, and grammar used by a people as their basic means of communication.

Gudgeon and tongue are semantically related. Sometimes you can replace term "Gudgeon" with "Tongue", this nouns are similar.