What is a parakeet?

[JaydeParrot]

Bit of a weird question, basically in the UK at least, birds like a budgie or a rosella would probably be considered a parakeet. I looked the word up in a parrot book and described parakeet as a small hookbill with long tail feathers. Admittedly that description's kinda confusing though, does that mean that cockatiels and most conures are parakeets too?

Where's the line where a hookbill is too big to be considered a parakeet, you wouldn't consider a macaw a parakeet right?

I read in another parrot book where there was a subtitle called parakeet where it talked about budgies, cockatiels and ring necks, and then another subtitle called parrot where it talked about senegal and sun conures- aren't ring necks, senegals and sun conures essentially the same size... Why is one of these a parakeet then?

So basically I was just wondering what the difference between a parrot and parakeet, I figure all parakeets are still parrots. But was wondering what prevents all parrots from being parrots?

Thanks.

[Wolf]

A parakeet is defined as a slender hookbill of small to medium size with long tail feathers. The term crosses several genera of parrots including pyrrhura and aratinga. Many conures are also referred to as parakeets, the Alexandrine is probably the largest part to also be referred to as a parakeet.
The Sun Conure is close to the size of the Senegal, but whereas the Sun Conure, has a slender body and a long tail, the Senegal has a stocky body and a short tail.
The cockatiel is of the same family as are Cockatoos and is the smallest of this family and they also have a moveable crest which parakeets do not.

[Pajarita]

The word 'parakeet' describes the same type of psittacine as the word conure and they both mean what Wolf said, a slender psittacine with a tapering tail longer than their body but, usually, parakeet is used to describe African and Asian species while conure is used for American ones.

Parakeet is thought to be derived from the Spanish word 'periquito' (small 'perico') which derives from the French word paroquet which, in turn, comes from the Italian parrucchetto, meaning small 'parrucca' (wig) and which is thought to be in reference to head plumage. Conure comes from 'Conurus' (kw^nos meaning cone and o'yra, tail), a genus which no longer exists in taxonomy and which used to include all aratingas and phyrruras (South and Central America species).