Unibody

noun

1. An automobile construction technique in which the body is integrated into a single unit with the chassis rather than having a separate body-on-frame.
2. A body of this type.
3. A shell that is the principal source of structural strength of an object; also, its design and construction.
4. A style of mobile phone, tablet, or laptop computer where the user cannot replace the battery because the device is manufactured as a single sealed unit.