Ástemma

As defined by A Concise Dictionary of Old Icelandic (Geir Zoëga):

ástemma

f. damming up of a river.

Possible runic inscription in Younger Futhark:ᛅᛋᛏᛁᛘᛘᛅ

Also available in related dictionaries:

This headword also appears in dictionaries of other languages closely related to Old Icelandic.

• Old Norse - Cleasby & Vigfusson Dictionary
• Old Norwegian - Johan Fritzner's Dictionary