Welford
“(A soldier from) the good army,” based on the Anglo-Saxon wel (good) and ferd (an army).
Welden
“From the spring pasture,” i.e., from the pasture having a spring or well, based on the Anglo-Saxon wella (spring, well) and denn (pasture). Also spelled Weldon.
Welby
“(From the village near the spring),” based on the Anglo-Saxon wella (spring, well) and by (a village).