Noun
an anchor used for semipermanent moorings; has a bowl-shaped head that will dig in however it falls
Source: WordNetA mushroom anchor will normally sink in the silt to the point where it has displaced its own weight in bottom material, thus greatly increasing its holding power. Source: Internet
Mushroom anchor Mushroom anchor on the lightship Portsmouth in Virginia The mushroom anchor is suitable where the seabed is composed of silt or fine sand. Source: Internet
The disadvantage of using deadweight anchors in conditions where a mushroom anchor could be used is that it needs to be around ten times the weight of the equivalent mushroom anchor. Source: Internet