Turn-on time is a term used in electronics to refer to the time taken by a device to switch on after power is supplied. It is an important specification for power electronic devices as it impacts the efficiency and reliability of the device. However, there are several synonyms for turn-on time that can be used to refer to the same concept. These include activation time, start-up time, initial response time, and response time. These terms refer to the amount of time taken for a device to become operational after it has received the required input. Understanding these synonyms can help engineers and technicians communicate more effectively when discussing and working with electronic devices.