IPA: /ˌæm.pjʊˈtiː/
KK: /ˈæmpjʊˌti/
A person who has lost one or more limbs due to surgery or injury.
The amputee participated in the marathon with a prosthetic leg.
Amputee is derived from the verb 'amputare' (from Latin, meaning to cut off) and the suffix '-ee' (meaning a person who is the recipient of an action). The word 'amputee' refers to a person who has had a limb cut off, thus being the recipient of the action of amputation.
Think of someone who has had a limb 'cut off' ('amputare') — the '-ee' indicates that this person is the one affected by that action.
No commonly confused words.