Akademik

shrewd
adj.
1 a showing astute powers of judgement; clever and judicious (a shrewd observer; made a shrewd guess). b (of a face etc.) shrewd-looking.
2 archaic a (of pain, cold, etc.) sharp, biting. b (of a blow, thrust, etc.) severe, hard. c mischievous; malicious.
Derivatives:
shrewdly adv. shrewdness n.
Etymology: ME, = malignant, f. SHREW in sense 'evil person or thing', or past part. of obs. shrew to curse, f. SHREW

Useful english dictionary. 2012.