Finger (the finger itself or fingertips); often used in formal or medical contexts, similar to 'finger'.
手指を怪我したので包帯を巻いた。
I injured my finger(s), so I wrapped them with a bandage.
ピアニストは手指の動きがとても器用だ。
A pianist's fingers move very skillfully.
手指の先まで十分に温めてから作業を始めた。
He warmed his fingers thoroughly before starting the work.
Hands and fingers collectively; refers to the whole hand or hand/finger region, often used in hygiene or medical contexts.
食事の前に手指をしっかり洗いましょう。
Wash your hands and fingers thoroughly before meals.
手指消毒は病院で徹底されている。
Hand disinfection is enforced thoroughly in the hospital.
リハビリで手指の運動を毎日行っている。
He does hand and finger exercises daily in rehab.