Where does “spien” come from?

spien (Middle English) comes from Old French espier, from Vulgar Latin spiare, from Frankish spehōn, from Proto-Germanic spehōną, from Proto-Indo-European speḱ- — to see, to look, to observe.

Ancestry of “spien”, step by step

StepLanguageWordMeaning
1Old Frenchespierto watch
2Vulgar Latinspiarepresent active infinitive of *spiō
3Frankishspehōnto spy, watch; to peer, to look, to spy
4Proto-Germanicspehōnąto peer, look, spy
5Proto-Indo-Europeanspeḱ-to see, to look, to observe

Words derived from “spien”

Every word from Proto-Indo-European speḱ- →Every word from Proto-Germanic spehōną →Every word from Frankish spehōn →