GS

• glide slope

  General

• Ground speed

  ATC

• Ground stop

  ATC

• snow pellets/small hail (less than 1/4”)

  METAR

GS has 4 meanings; the right one depends on context. A weather report, a NOTAM or an ATC clearance. Got a NOTAM full of contractions? Paste it into the decoder.

Source: FAA Order JO 7340.2 Contractions. Not for operational use.