A laser that operates by analogy with an electronic waterfall, with electrons cascading down a series of small steps emitting a photon at each step.

(slang, potentially offensive) One made powerless or ineffective, as by nerves, panic, stress or exhaustion.

A helmet. / A hard structure on the head of some birds, such as the hornbill or cassowary.

Wet, heavy and often sticky snow, which makes skiing and snowboarding difficult.

Castle-like: built or shaped like a castle. / (engineering) Having grooves or recesses on an upper face. / Castled: having or furnished with castles. / (rare) Housed or kept in a castle.

(obsolete) Synonym of enclosed, when used for fountains, cisterns, &c.

A castrated man; a eunuch.

(transitive) To remove the testicles of a person or animal. / (transitive) To remove the ovaries and/or uterus of an animal.

Any of the hereditary social classes and subclasses of South Asian societies. / A separate and fixed order or class of persons in society who chiefly associate with each other.

(surgery) The act of removing the testicles. / (figuratively) Any act that removes power from a person (particularly a man) or entity.