There are a total of 20 3-letter words containing 'se', and the number may vary in different dictionaries. You can specify the dictionary and order.

• ese ₃
• ose ₃
• sea ₃
• sec ₆
• see ₃
• sei ₃
• sel ₄
• sen ₄
• seq ₁₂
• ser ₃
• ses ₃
• set ₃
• sev ₇
• sew ₆
• sex ₁₀
• sez ₁₂
• use ₄
• seg ₄
• sed ₄
• sey ₆

There are 20 3-letter words containing "se" in the well-known word game dictionary, 15 in the Scrabble US (US/Canada/Thailand - TWL/NWL) dictionary, and 16 in the Scrabble UK (International - SOWPODS/CSW) dictionary, and 17 in the Words with Friends (WWF) dictionary.