co·gent 
(kōjənt)
(kōjənt)adj.
Appealing to the intellect or powers of reasoning; convincing: a cogent argument. See Synonyms at valid.
[Latin cōgēns, cōgent-, present participle of cōgere, to force : co-, co- + agere, to drive; see ag- in the Appendix of Indo-European roots.]
cogen·cy (-jən-sē) n.
cogent·ly adv.
- standing wave
- Standish
- stand off
- standoff
- standoffish
- standoffishness
- stand on
- stand (one's) ground
- stand one's ground
- stand on head
- stand on (one's) head
- stand on one's head
- stand on one's own feet
- stand on (one's) own/two feet
- stand on one's two feet
- stand on own feet
- stand on two feet
- stand out
- standout
- stand over
- stand pat
- standpat
- standpatter
- standpipe
- standpoint