Etymology
Two main origins:
* From the Middle English personal name Thedere, Teddere, which is either from Old English Þēodhere, from þēod (“nation”) + here (“army”), or from the Norman personal name Theudher, which shares the same etymology.
* Occupational surname from Middle English teddere (“one who teds”), from the verb tedden (“to ted, to spread hay for drying”).