a projection or ridge that suggests a keel

the median ridge on the breastbone of birds that fly

one of the main longitudinal beams (or plates) of the hull of a vessel; can extend vertically into the water to provide lateral stability

walk as if unable to control one's movements

a pointed arch having an S-shape on both sides

turn over and fall

shaped in the form of the keel of a boat

river boat with a shallow draught and a keel but no sails; used to carry freight; moved by rowing or punting or towing

having a ridge or shaped like a ridge or suggesting the keel of a ship

Eurasian bulbous plant

a longitudinal beam connected to the keel of ship to strengthen it