A tied knot, often in a string, rope, or cord; can refer to the physical knot itself or the act of tying it.
The knot in the string is tight and won't come undone.
Please tighten the knot firmly.
Standard kanji spelling for a knot, combining 結い (tying) and 目 (point/spot).
Variant spelling omitting the okurigana い; less common but still encountered.
Compound of 結い (yui, 'tying', from verb 結う) and 目 (me, 'point, spot'). The exact historical derivation is uncertain, but the word transparently means 'tying point'.