﹛﹛isentropic exponent,等熵指數ISFET ion transducer[sensor],場效應管（式）离子傳感器
isoabsorptive point,等吸收點
isobaric mass-change determination,等壓質量變化測定
isobaric weight-change curve,等壓重量變化曲線
isobaric weight-change determination,等壓重量變化測定
isolated amplifier,隔离放大器
isolated analogue input,隔离的模擬輸入
isolated junction,絕緣端
isolated junction type sheathed thermocouple,絕緣型鎧裝熱電偶
isolated system,孤立系統
isolating valve,隔斷閥
isolator,隔离器
isopotential point,等電位點
isothermal point,恒溫式熱量計
isothermal gas chromatography,等溫層跟蹤儀
isothermal weight-change curve,等溫重量變化曲線
isothermal weight-change determination,等溫重量變化測定
isotope dilution mass spectrometry,同位素稀釋質譜法
isotope mass spectrometer,同位素質譜計
isotope peak,同位素峰
isotope ratio measurement,同位素丰度測定
item,項（目）
iteration chromatography,核對色譜法
ivory point,象牙針尖
jaw,鉗口
jerk transducer(sensor),加速度傳感器
jet orifice separator,噴嘴分离器
jet recorder,噴射式記錄儀
job,作業
Jordan sunshine recorder,暗筒日照計；喬唐日照計
journal,軸頸
journal axis,軸頸中心線
journal centre,軸頸中心
joy stick,操縱杆
junction class (of thermocouple),（熱電偶的）端的類型
junction style(of thermocouple),（熱電偶的）端的形式
junction type zinc oxide varstor,結型氧化鋅電壓敏電阻器
Kaiser effect,凱撒效應
karma foil,卡瑪箔
Kelvin,開爾文
Kelvin(double)bridge,開爾文（雙臂）電橋
Kelvin temperature scale,開氏溫標
Kew pattern barometer,寇烏气壓表
key in ,鍵盤輸入
keyboard,鍵盤
keyboard processor,鍵盤處理器
keystone-type distortion,梯形畸變
kinematic viscosity,運動粘度
kinetic energy coefficient,動能系數
knee point voltage,拐點電壓
knife dege contact width,刀子接触寬度
knife edge curvature radius,刀子曲率半徑
knife-edge pointer,刀形指針
knives,刀子
knives linear,刀子聯線
Knoop hardness number,努普硬度值
Knoop hardness penetrator,努普硬度壓頭
knowledge acquisition,知識獲取
knowledge aided protocol automation,知識輔助協議自動化
knowledge base,知識庫
knowledge base management system,知識庫管理系統
knowledge engineering,知識工程
knowledge inference,知識推理
knowledge model,知識模型
knowledge representation,知識表達
Knudsen burette,克努森滴定管
Knudsen pipette,克努森移液管
L grader,L分級器
LaB6 cathode,六硼化鑭陰极
label,標號
labelling,加標
laboratory reliability test,實驗室可靠性試驗
laboratory salinometer,實驗室鹽度計
ladder diagram,梯形圖
lag compensation,滯后補償
lag module,滯后組件
lag network,滯后网絡
lag-lead compensation,滯后超前補償
Lagrangian method,拉格朗日法
Laman spectrophotometer,拉曼分光光度計
laminar low,層流
laminated glass window,層壓玻璃觀察窗
laminated magnet,積層磁鐵
landing impact testing machine,落錘式衝擊試驗机
Laplace transform,拉普拉斯變換
Laplace-Gauss distribution,拉普拉斯﹛高斯分布
large scale system,大系統
large scale system cybernetics,大系統控制論
large volume sampler,大容量采水器
laser,激光器
laser alignment instrument,激光導向儀
laser anemometer,激光風速計
laser atomizer,激光原子化器
laser beam ionization,激光電离
laser ceilometer,激光測云儀
laser distance meter,激光測距儀
laser ellipseness measuring instrument,激光橢圓度測量儀
laser fluorescence detector,激光熒光探測儀
laser geodynamic satellite（LAGEDS),激光測地衛星
