What does Rud stand for?

Rudolph - Botanist in plant scientific name (HUH)

Radar Unit Diagnostics (SAUS)

Rational Use of Drugs (DB)

Recently Used Directory - Computer science (MHDI)

Recurrent Ulcer of the Duodenal Bulb - Medicine (DMAA)

Rudder (AAG)

Rundi - Language symbol (ETLW)

Rutland, VT - Amtrak rail station code