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one o'clock
once; at one time; formerly; before
for a time; for a while; for the time being; for the moment; temporarily
a time; one time; once
「一時」 has another reading with different meanings.
困難な時期もあったが一時は諦めようと思った。
At one point, I thought about giving up.
一時、彼はその業界の頂点に立っていた。
There was a time when he stood at the top of that industry.
会議は一時に始まります。
The meeting starts at one o'clock.