～がる
～がる · ～garu · JLPT N5 · noun
feel
～がる = adjective stem + garu: to show signs of feeling it (others, not you)
Attach がる to an adjective stem to say someone else outwardly acts out a feeling: 寒い (cold) → 寒がる (acts cold), 欲しい (want) → 欲しがる (shows wanting). Japanese avoids stating another person's inner feelings directly, so がる reports the visible behaviour.