Initialism of Ornithine transcarbamylase deficiency.
"The newborn screening test revealed an otc disorder, confirming a diagnosis of ornithine transcarbamylase deficiency in the infant."
In plain English: Otc is short for over-the-counter, which means you can buy certain medicines and products at regular stores without needing a doctor's prescription.
"He bought some ibuprofen at the pharmacy without needing a prescription, which made it an otc option for his headache."
Initialism of over-the-counter.
"The patient was prescribed otc medication to manage his mild allergies without a doctor's visit."
In plain English: Otc means something that is done without following official rules or procedures.
"The store sells cheap otc painkillers without needing a prescription."
Initialism of Officers Training Corps. (part of the British Army)
"Many young recruits joined the OTC to gain military training before enlisting in the regular army."
Initialism of on the cheek.
"The nurse gently placed her hand otc to comfort the crying child."