boat·swain also bo's'n or bos'n or bo·sun (bōsən)
A warrant officer or petty officer in charge of a ship's rigging, anchors, cables, and deck crew.
Usage Note: The word boatswain is pronounced as a single word with two syllables (bōsən). People with sea legs have a long tradition of spelling the word as bosun, bo's'n, and bos'n to reflect the salty pronunciation. This of course has not prevented landlubbers from using the incorrect two-word pronunciation (bōtswān′). Many other nautical words have similarly tricky shipboard pronunciations, including bowline, pronounced (bōlĭn); forecastle, pronounced (fōksəl) and sometimes spelled fo'c's'le; gunwale, pronounced (gŭnəl) and also sometimes spelled gunnel; mainsail, pronounced (mānsəl); and topgallant, pronounced (tə-gălənt). With the exception of gunwale, however, all of these terms can be correctly pronounced as if they were two words.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.