Etymology

Noun

1. A line of people, vehicles or other objects, in which one at the front end is dealt with first, the one behind is dealt with next, and so on, and which newcomers join at the opposite end (the back).
   • 1916, John Buchan, Greenmantle, Chapter 5,

     I was absent-minded at the moment and was last in the queue.

2. A waiting list or other means of organizing people or objects into a first-come-first-served order.
3. A data structure in which objects are added to one end, called the tail, and removed from the other, called the head (- a FIFO queue). The term can also refer to a LIFO queue or stack where these ends coincide.
   • 2005, David Flanagan, Java in a Nutshell, p. 234,

     Queue implementations are commonly based on insertion order as in first-in, first-out (FIFO) queues or last-in, first-out queues (LIFO queues are also known as stacks).

4. A men's hairstyle whose primary attribute is a braid (sometimes a ponytail, after the French meaning) at the back of the head, such as that worn by men in Imperial China.
   • 1889, Arthur Conan Doyle, Micah Clarke, Chapter XIX

     , there were seated astraddle the whole hundred of the baronet's musqueteers, each engaged in plaiting into a queue the hair of the man who sat in front of him.

   • 1912, Herbert Allen Giles, China and the Manchus, Chapter III — Shun Chih,

     A large number of loyal officials, rather than shave the front part of the head and wear the Manchu queue, voluntarily shaved the whole head,

Verb

1. To put oneself or itself at the end of a waiting line.
2. To arrange themselves into a physical waiting queue.
3. To add to a queue data structure.

Noun

1. tail
2. queue, line
3. cue
4. cock, dick