frostfish

from The Century Dictionary.

• noun The tomcod, Microgadus tomcodus: so called from its appearance in the fall, as frost sets in. See cut under Microgadus.
• noun The scabbard-fish, Lepidopus argenteus.

from the GNU version of the Collaborative International Dictionary of English.

• noun Local, U. S., Local, U. S. The tomcod; -- so called because it is abundant on the New England coast in autumn at about the commencement of frost. See tomcod.
• noun Local, U. S. The smelt.
• noun A name applied in New Zealand to the scabbard fish (Lepidotus) valued as a food fish.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The tomcod (so called because it is abundant on the New England coast in autumn at about the commencement of frost).
• noun US, dialect The smelt.
• noun New Zealand The scabbardfish.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun long-bodied marine fishes having a long whiplike scaleless body and sharp teeth; closely related to snake mackerel