Thanks!
"Tick tock" isn't simply a holdover, though. Every language has their own version of "tick tock" and people do actually perceive a difference. This is one of the first things studied by the new field of Psychology in the 19th century. It is very, very well studied.We will split the ticking into tick-tock even if it is totally equal (this has been VERY well studied, for almost 150 years now) Faster ticks may become 6/8 or another metrical grouping, and you can induce a particular way of hearing it by differentiating the sounds by modulating the tone, volume or moving one ahead or behind the beat.
In my 2nd book,
Start Playing Drums, I talk about what it means specifically for drummers. The "Tick"is the downbeat, it is played with the bass drum, and feels heavy, or gravity. The "tock" is the backbeat, commonly played with the snare in American musics, and feels light, or anti-gravity. All American music starts with the downbeat on beat 1*. Caribbean music, such as Reggae or Samba, typically starts on the back beat and has the downbeat on beat 2. This is at odds to what you learned about rhythm at the University, which says that the back beat is just a lesser form of the down beat. They are not the same thing at all, and their relative strengths help define the overall feel of the rhythm.
*(note: some people use downbeat to also mean the 1st beat in a piece, or the first beat in a bar. These are different meanings for the same word. I'm not using it to refer to the first beat of the bar, or the start time of the show)