誓い|ちかいchikai[0]heiban (flat)

1. nounoath; vow

• Related決意けついWrittenWritten/formal prose. Refers to making up one's mind, as in 「決意を固める」; it stresses an inner decision, while 「誓い」 is a solemn vow sworn to a god, a person, or oneself.
• Related決心けっしんNeutralNeutral and common in daily use for making up one's mind; 「誓い」 is more solemn and carries the sense of taking an oath, and can also be a vow made to oneself.

Use 「誓い」 for a solemn vow, as in 「誓いを立てる」; to say you have made up your own mind, use 「決心」 in everyday speech or 「決意」 in written/formal prose.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. （他人たにんや自分じぶん、神仏しんぶつなどに）心こころに決きめたことを告つげること。
2. 「ちかう」の連用形れんようけい。