The Collaborative International Dictionary of English v.0.48:
Dexter \Dex"ter\ (d[e^]ks"t[~e]r), a. [L.,; akin to Gr. ?, ?,
Skr. dakshi[.n]a (cf. daksh to be strong, suit); Goth.
taihswa, OHG. zeso. Cf. Dexterous.]
1. Pertaining to, or situated on, the right hand; right, as
opposed to sinister, or left.
On sounding wings a dexter eagle flew. --Pope.
2. (Her.) On the right-hand side of a shield, i. e., towards
the right hand of its wearer. To a spectator in front, as
in a pictorial representation, this would be the left
Dexter chief, or Dexter point (Her.), a point in the
dexter upper corner of the shield, being in the dexter
extremity of the chief, as A in the cut.
Dexter base, a point in the dexter lower part or base of
the shield, as B in the cut.