transition; transitional state; change from old to new
The main modern use refers to a state or period of changing from one condition, system, or era to another. Often appears in compounds such as 過渡期 or in 過渡的, meaning transitional or temporary.
Society is in a transitional period of major change.
This industry is now in a transitional period.
Until the new system takes hold, transitional measures are necessary.
Literal sense connected with crossing over water or a ferry; uncommon in modern everyday use compared with the figurative 'transition' sense.
In older usage, 過渡 can refer to crossing a river or to a ferry.
This is nothing more than a transitional measure.
転換 emphasizes the act or turning point of changing direction, whereas 過渡 emphasizes the ongoing transitional interval itself.
一時的 simply means temporary, while 過渡的 (from 過渡) specifically implies temporariness caused by being in a state of transition.
過渡 (transition, かと) and 過度 (excessive, かど) look and sound similar but mean completely different things—one is about change over time, the other about too much of something.
A Sino-Japanese compound written with 過, associated with passing or going beyond, and 渡, associated with crossing. The literal idea of crossing is reflected in the rare 'crossing/ferry' sense, and the modern figurative use extends this to passing from one state to another.