ache, pain, tingle, fester
疼 centers on a persistent, often dull or throbbing bodily discomfort: an ache, a pain, or a tingling sensation. The fester sense extends this to a wound that is painfully inflamed.
疼 combines 疒 (sickness) with 冬, which likely contributes the sound トウ. The character expresses a painful condition associated with illness.
The sickness enclosure 疒 wraps around 冬 (winter). Picture a deep winter ache that settles into your bones, a dull pain that lingers like the cold.
For トウ, imagine touching a sore spot and feeling a sharp toe-curling ache: toe -> トウ, and the pain makes you wince.
throbbing pain
to throb (with pain); to ache; to smart; to twinge
ache; twinge
International Association for the Study of Pain; IASP
dyspareunia; painful intercourse
chronic pain
American Pain Society; APS
complex regional pain syndrome; CRPS