A retractable fin keel used on sailboats to prevent drifting to leeward.

synonyms: centreboard, drop keel, sliding keel.

Roget 211: base, basement; plinth, dado, wainscot; baseboard, mopboard^†; bedrock, hardpan [U.S.]; foundation etc. (support) 215; substructure, substratum, ground, earth, pavement, floor, paving, flag, carped, ground floor, deck; footing, ground work, basis; hold, bilge.    bottom, nadir, foot, sole, toe, hoof, keel, root; centerboard.    ... show more

Dutch: midzwaard, kielzwaard
Polish: miecz szybrowy