Token

*deik- "to show," also "pronounce solemnly."
1. a thing serving as a visible or tangible representation of a fact, quality, feeling, etc.
2. a voucher that can be exchanged for goods or services, typically one given as a gift or forming part of a promotional offer.
token (adj.)
"nominal," 1915, from token (n.). In integration sense, first recorded 1960.
token (n.)Old English tacen "sign, symbol, evidence" (related to verb tæcan "show, explain, teach"), from Proto-Germanic *taiknam (source also of Old Saxon tekan, Old Norse teikn "zodiac sign, omen, token," Old Frisian tekan, Middle Dutch teken, Dutch teken, Old High German zeihhan, German zeichen, Gothic taikn "sign, token"), from PIE root *deik- "to show," also "pronounce solemnly."Meaning "coin-like piece of stamped metal" is first recorded 1590s. Older sense of "evidence" is retained in by the same token (mid-15c.), originally "introducing a corroborating circumstance" [OED].