- U-turn (noun) :a complete change in policy or behaviour, usually one that is embarrassing; a turn of 180° that a vehicle makes so that it can move forwards in the opposite direction การเปลี่ยนโดยสิ้นเชิง, การเลี้ยวหรือทางเลี้ยวเป็นรูปตัว "U"
- U.N. High Commissioner for Refugees (noun) :a UN agency which helps refugees at the request of a government or the UN itself สำนักงานข้าหลวงใหญ่เพื่อผู้ลี้ภัยแห่งสหประชาชาติ
- uber :of the greatest or best kind; to a very large degree
- ubiquitous :found everywhere, existing everywhere
- ubiquitous (adj) :seeming to be everywhere or in several places at the same time ซึ่งมีอยู่ทุกหนทุกแห่ง
- UFO (noun) :the abbreviation for ‘Unidentified Flying Object’ (a strange object that some people claim to have seen in the sky and believe is a spacecraft from another planet) จานบินของมนุษย์ต่างดาว (คำย่อ Unidentified Flying Object)
- ugly :unpleasant to look at น่าเกลียด, ขี้เหร่, ไม่สวย
- ulcer (noun) :a sore area on the outside of the body or on the surface of an organ inside the body which is painful and may bleed or produce a poisonous substance แผลเปื่อย, แผลพุพอง
- ulterior :that somebody keeps hidden and does not admit ซึ่งลี้ลับ, ซึ่งซ่อนเร้น, ซึ่งแอบแฝง
- ultilities :services such as the providing of water, electricity, gas, etc. สาธารณูปโภค
- ultimate :final, after a series of things have happened ท้ายที่สุด, ตอนสุดท้าย, ในที่สุด
- ultimate :most extreme; best, worst, greatest, most important, etc ที่สุด
- ultimately :finally, after a series of things have happened ท้ายที่สุด, ตอนสุดท้าย, ในที่สุด
- ultimatum :a statement that orders someone to do something and threatens to punish or attack them if they do not คำขาด
- ultra- :extremely ที่สุด
- ultra-athlete :a person who competes in and trains for ultra-triathlons long-distance triathlons: "The term generally refers to all triathlon events of distance greater than the Ironman Triathlon. Thus, every ultra triathlon event must involve more than 2.4 miles (3.86 km) of swimming, 112 miles (180.25 km) of cycling, and a full marathon (26.2 mi or 42.2 km) of running.... swimming, cycling and running may take place on consecutive days" (Source: Wikipedia)