Old English tin, from Proto-Germanic *tinom (cf. Middle Dutch and Dutch tin, Old High German zin, German Zinn, Old Norse tin), of unknown origin, not found outside Germanic.
Other Indo-European languages often have separate words for "tin" as a raw metal and "tin plate;" e.g. French étain, fer-blanc. Pliny refers to tin as plumbum album "white lead," and for centuries it was regarded as a form of silver debased by lead.
The chemical symbol Sn is from Late Latin stannum (see stannic). Tin-type in photography is from 1864. Tin ear "lack of musical discernment" is from 1909. Tin Lizzie "early Ford, especially a Model T," first recorded 1915.