There are a total of 13 6-letter words containing 'rail', and the number may vary in different dictionaries. You can specify the dictionary and order.

• brails ₁₀
• derail ₈
• drails ₈
• frails ₁₀
• grails ₉
• railed ₈
• railer ₇
• serail ₇
• trails ₇
• graile ₇
• railes ₆
• railly ₉
• rerail ₆

There are 13 6-letter words containing rail in the well-known word game dictionary, 9 in the Scrabble US (US/Canada/Thailand - TWL/NWL) dictionary, and 13 in the Scrabble UK (International - SOWPODS/CSW) dictionary, and 9 in the Words with Friends (WWF) dictionary.