Rh

1. rhesus (factor).

   Rh negative

symbol

the chemical element rhodium.

abbreviation, unpunctuated

right hand.

noun, symbol

the chemical element of atomic number 45, a hard silvery-white metal of the transition series, typically occurring in association with platinum.

early 19th century: modern Latin, from Greek rhodon ‘rose’ (from the colour of the solution of its salts).