| n. | 1. | A pin used to prevent the wheel of a vehicle from sliding off the axletree. |
| Noun | 1. | linchpin - a central cohesive source of support and stability; "faith is his anchor"; "the keystone of campaign reform was the ban on soft money"; "he is the linchpin of this firm" |
| 2. | linchpin - pin inserted through an axletree to hold a wheel on Synonyms: lynchpin |