Problems and losses that do not reach the attention cause no worries and no grief.

A leather head covering with earflaps used by early aviators.

plural of heel turn

(rail transport) To haul a train with two locomotives at the head end.

(idiomatic) Incredible, overwhelming.

A species of sunbird, Cyanomitra verticalis, of tropical Africa.

plural of green-headed sunbird

A balaclava (type of headgear).

An agency of the United Nations responsible for international public health

A mining helmet, a hard hat worn by miners that usually carries a light on the front. / Eggcorn of pith helmet.