- Woillez's disease (acute idiopathic pulmonary congestion) 518.52
- Wolff-Parkinson-White syndrome (anomalous atrioventricular excitation) 426.7
- Wolhynian fever 083.1
- Wolman's disease (primary familial xanthomatosis) 272.7
- Wood asthma 495.8
- Wool-sorters' disease 022.1
- Woolly, wooly hair (congenital) (nevus) 757.4
- Word
- Worm(s) (colic) (fever) (infection) (infestation) (see also Infestation) 128.9
- Worm-eaten soles 102.3
- Worn out (see also Exhaustion) 780.79
- Wound, open (by cutting or piercing instrument) (by firearms) (cut) (dissection) (incised) (laceration) (penetration) (perforating) (puncture) (with initial hemorrhage, not internal) 879.8
- Wright's syndrome (hyperabduction) 447.8
- Wringer injury - see Crush injury, by site
- Wrinkling of skin 701.8
- Wrist - see also condition
- Wrong drug (given in error) NEC 977.9
- Wry neck - see also Torticollis
- Wuchereria infestation 125.0
- Wuchereriasis 125.0
- Wuchereriosis 125.0
- Wuchernde struma langhans (M8332/3) 193
