KanjiJLPT N1
Regret (Of Loss)

pity, be sparing of, frugal, stingy, regret

Mnemonic

Your spirit keeps drifting back to once upon a time—replaying scenes of people and places now gone. Each memory twists deeper, flooding you with regret (of loss). If only you'd savored those moments instead of letting them slip away, your spirit wouldn't ache like this.
Additional thoughts
The heart radical (spirit) literally feels the weight of the past (once upon a time). The pairing is natural: an emotional core reliving bygone days creates the perfect recipe for lamenting what's gone.
Quick recall
A spirit haunted by once upon a time memories aches with regret (of loss).

Details

The keyword for 惜 is regret (of loss). This kanji conveys the feeling of sorrow or reluctance that arises when something valuable is lost, wasted, or let go. It captures the sense of lamenting that something precious has slipped away or was not fully appreciated while it was present. The emotion expressed is not mere sadness but a specific pang of wishing things could have been preserved or cherished more.
On'yomi
せき
Kun'yomi
お.しい、お.しむ