(metallurgy) A kind of tool steel, invented in the early 20th century, which retains its hardness and temper at high temperatures (at which previous kinds of tool steel would soften), thus allowing cutters made from it to be employed at higher cutting speeds than were previously practical.

A title given to certain female members of a royal family, abbreviated HRH.

A title given to certain male members of a royal family, abbreviated HRH.

plural of high-density lipoprotein

(uncountable) Any or all of several formats of television system having a higher resolution than traditional ones / (countable) A television set that employs such a system

(education) A school for children who have completed elementary school or grade school, but are not yet old enough for high school. In the US, it often includes grades 7 and 8, and possibly also 6 or 9.

(idiomatic) short; especially relating to when the subject was a small child

plural of junior high school

plural of high-definition television

Fruit that, because of its height from the ground, is more difficult to harvest / (by extension) Anything that is difficult to achieve, and which is put off while simpler alternatives are still available