1) Siamese measure 2) Unit of area 
A ngan (งาน, {RTGS|ngan}, IPA) is a unit of area, equal to 400 square metres (20 m × 20 m), used for measuring land or property area. Its current size is precisely derived from the metre, but is neither part of nor recognized by the modern metric system, the International System (SI). The ngan equals 1/4 rai or 100 tarangwa aka square wa, v...