free-free
adjective
1 Mechanics designating a linear structure which can vibrate unconstrained at each end.
2 Physics relating to an interaction (usually emission or absorption of a photon) in which the particle concerned is free (not in a bound state) both before and after it.
Origin
Late 19th century; earliest use found in American Journal of Mathematics.
- on the edge of one's seat
- on the face of it
- on the fiddle
- on-the-field
- on the flat
- on the fly
- on the front foot
- on the game
- on the go
- on the grog
- on the ground
- on the hip
- on the home front
- on the hoof
- on the hook for
- on the hop
- on the horizon
- on the horn
- on the horns of a dilemma
- on the hour
- on the house
- on the improve
- on the increase
- on the inside
- on the instant