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In physics, position as a function of time is generally called d(t) or s(t). Using "d" is pretty intuitive, however I haven't been able to figure out why "s" is used as well. Is it possibly based on another language?

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it could be based on the german word 'Strecke', but I don't think this convention is that strict in the first place. – luksen Feb 23 '12 at 18:41
Yes, $s$ stands for the german word Strecke, and $d$ for distance. – Qmechanic Feb 23 '12 at 18:45
@luksen & Qmechanic Thanks! – jli Feb 24 '12 at 21:06
up vote 4 down vote accepted

As commenters have pointed out, it's German Strecke.

Note that $s$ is for displacement, whereas $d$ is for distance. Distance is the distance along the path traveled by a body, whereas displacement is the birds-eye distance traveled. Displacement can also be negative in 1-D, depending upon your reference positive direction.

For some reason, Strecke actually means distance, not displacement, but its symbol is used for displacement.

You might want to check out this paper, it's got an analysis of the naming, mainly for electrodynamic units. A few symbols from the table at the end of the paper: $c$ (speed of light) comes from Latin celeritas; $I$ (current) comes from "intensity of current" in French (intensite du courant). The $\mathbf{A}$-potential, $\mathbf{B}$-field, $\mathbf{H}$-field got their symbols from the alphabetic order of the others.

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Community wiki as I'm just answer-ifying the comments. – Manishearth Feb 24 '12 at 1:24
Comment to the answer(v1): Note that Strecke and distance usually denote non-negative quantities, while a displacement is a relative change in position, and therefore can be both positive and negative. – Qmechanic Feb 24 '12 at 1:34
I've added it, though you could have added it yourself. It's community wiki for that reason; I myself don't know much about it. – Manishearth Feb 24 '12 at 2:02

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