back|bone

back|bone «BAK _BOHN», noun.

1. the main bone along the middle of the back in humans and other mammals, birds, reptiles, amphibians, and fishes; spine; spinal column. The backbone consists of many small bones, called vertebrae, held together by ligaments.

2. anything like a backbone. The backbone or spine of a book is where the sections or signatures are gathered and glued together and attached to the covers or case. »

The backbones of nucleotide chains are separated by a constant distance throughout the length of the molecule (Isaac Asimov).

3. Figurative. the most important part; chief support; basis: »

Scientific research is the backbone of modern industrial progress.

SYNONYM(S): foundation, bedrock.

4. Figurative. strength of character; firmness: »

A coward lacks the backbone to stand up for his beliefs.

SYNONYM(S): fortitude, hardihood.

–back´bone´less, adjective.