Y1

Y1 has several uses including: and also :
 * Boeing Y1, the anticipated replacement for the company's existing Boeing 737 airliner
 * Great Northern Y-1, an electric locomotive used by the Great Northern Railway.
 * Y1 adrenocortical cell, a mouse cell line
 * Y1 (railcar), a Swedish-made diesel multiple unit train
 * LNER Class Y1, a class of British steam locomotives
 * Y1 (tobacco), a genetically altered tobacco
 * Blue Air IATA airline code
 * y1, Yellow seed 1, a sorghum gene implied in the phlobaphene pigments pathway