IPA: /ˈblʌd.məˌbiːl/
KK: /ˈblʌdˌmoʊbil/
A vehicle that is specially designed and equipped to collect blood from people who want to donate it.
The bloodmobile parked outside the shopping center to encourage people to donate blood.
Bloodmobile is formed from "blood" (from Old English "blōd", meaning the red fluid that circulates in the bodies of humans and animals) and "mobile" (from Latin "mobilis", meaning movable or capable of moving). The word "bloodmobile" refers to a vehicle that is designed to move and collect blood donations.
Think of a vehicle that is 'movable' ('mobile') and is specifically for collecting 'blood' — that's what a bloodmobile is.