Usually involves feeling of fear or insecurity. The loss of confidence in things that have always been stable or dependable in the past â this includes things such as a relationship, your personality structure, health, etc; so the breakdown of opinions, attitudes or relationships which seemed so dependable and you have taken for granted.
Crests and troughs. Waves have moving crests (or peaks) and troughs. A crest is the highest point the medium rises to and a trough is the lowest point the medium sinks to. Crests and troughs on a transverse wave are shown in Figure 1. A crest is a point on the wave where the displacement of the medium is at a maximum.
A crest is a showy tuft of feathers on the head of a bird. It's easy to identify a male cardinal by its bright red color and the tufted crest on its head. The Latin word crista, which crest comes from, means tuft or comb.An animal's crest can be feathers, fur, skin, or a comb like a rooster's. Something that resembles such a feature can also be called a crest, such as a plume on an old-fashioned helmet.