merchant seaman

As used in this section, the term "merchant seaman" means any individual who was employed as a seaman or crew member on any vessel registered under the laws of the United States, or under the laws of any government friendly to the United States during World War II, and who was a citizen of the United States on and after December 7, 1941, to the date of his death or the date of filing claim under this section; except any such individual who is entitled to, or who has received, benefits under section 4104 of this title as a "civilian American citizen".