Si·ha·sa·pa 
(sə-häsə-pə)
(sə-häsə-pə)n. pl. Sihasapa or Si·ha·sa·pas
A member of a Native American people constituting a subdivision of the Lakota, with a present-day population in South Dakota. Also called Blackfoot, Blackfoot Sioux.
- on (one's) toes
- on one's toes
- on (one's) uppers
- on one's uppers
- on one's way
- on one/the onehand
- on order
- on own
- on own account
- on own ground
- on own hook
- on own initiative
- on pain of
- on paper
- on pins and needles
- on principle
- on purpose
- on radar screen
- on radar screen
- on record
- on relief
- on report
- on request
- onrush
- onrushing