numb (adj.) Look up numb at Dictionary.com
c.1400, nome, "deprived of motion or feeling," literally "taken, seized," from past participle of nimen "to take, seize," from Old English niman "to take, catch, grasp" (see nimble). The extraneous -b (to conform to comb, limb, etc.) appeared 17c. The notion is of being "taken" with palsy, shock, and especially cold. Figurative use from 1560s.
numb (v.) Look up numb at Dictionary.com
1550s, from numb (adj.). Related: Numbed; numbing.