groove 
(grv)
(grv)n.
1. A long narrow furrow or channel.
2. The spiral track cut into a phonograph record for the stylus to follow.
3. Slang A settled routine: got into the groove of a nine-to-five job.
4. Slang A situation or an activity that one enjoys or to which one is especially well suited: found his groove playing bass in a trio.
5. Slang A very pleasurable experience.
v. grooved, groov·ing, grooves
v.tr.
1. To cut a groove or grooves in.
2. Baseball To throw (a pitch) over the middle of home plate, where it is likely to be hit.
v.intr.
Slang
Idiom: Slang
1.
a. To take great pleasure or satisfaction; enjoy oneself: just sitting around, grooving on the music.
b. To be affected with pleasurable excitement.
2. To react or interact harmoniously.
in the groove Slang
Performing exceptionally well.
[Middle English groof, mining shaft, probably from Middle Dutch groeve, ditch; see ghrebh-2 in the Appendix of Indo-European roots.]