shiku-shiku
A nagging, constant pain in the abdomen — not sharp like kiri-kiri, but a slow, persistent ache that won't go away.
💡Waking up with a stomach ache — 'My stomach has been shiku-shiku aching since last night.'
昨日からお腹がしくしく痛む。
My stomach has been aching shiku-shiku since yesterday.
I've had a ___ ache in my stomach all day.
一日中お腹が○○痛い。