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half-staff vs. half-mast

half-staff

[haf-staf, hahf-stahf] / ˈhæfˈstæf, ˈhɑfˈstɑf /

noun

half-mast

[haf-mast, hahf-mahst] / ˈhæfˈmæst, ˈhɑfˈmɑst /

a position approximately halfway between the top of a mast, staff, etc., and its base.

to place (a flag) at half-mast, as a mark of respect for the dead or as a signal of distress.