pos·til·ion also pos·til·lion 
(pō-stĭlyən, pŏ-)
(pō-stĭlyən, pŏ-)n.
One who rides the near horse of the leaders to guide the horses drawing a coach.
[French postillon, from Italian postiglione, from posta, mail, from Old Italian, mail station; see POST3.]
- special operator
- special pleading
- special relativity
- special sense
- special session
- special team
- special theory of relativity
- specialty
- speciate
- speciation
- speciational
- specie
- species
- speciesism
- speciesist
- species-specific
- species-specificity
- specifiable
- specific
- specifically
- specification
- specific epithet
- specific gravity
- specific heat
- specific humidity