温い
ぬるい · nurui · JLPT N5 · i-adj
lukewarm
🍵 nurui sounds like new-ROOM-temp: tea left out, neither hot nor cold
温 is the warm kanji (as in 温度, temperature) and い marks an adjective. Read ぬるい, it means warm that has slipped to tepid: tea or bath water that should be hotter. It also describes a soft, half-hearted attitude.