Out on a LIMB is an idiom that means to take a risk or to do something without the support of others. It is often used to describe a situation where someone is taking a chance and is uncertain of the outcome. The crossword solution for this term is 'LIMB, ' which refers to a branch of a tree. This phrase is often used to describe a person who is taking a risk and is uncertain of the outcome, as if they are standing on a branch of a tree and could fall at any moment.