Columns in Excel are too narrow and initially the wrong way round (5)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

Initial letters of E [xcel] A [re] T [oo] N [arrow] A [nd], all reversed (the wrong way round). Plural of anta: a square pillar (column) at the end of a wall or at the side of a doorway.