2. (verb) to be acrid, acidic, bitter, sour.
Ka tae māua ki te moana mate, te wāhi i panā atu rā a Rota, ka inu i te wai, a mangeo ana (KO 1/4/1882:2). / We arrived at the Dead Sea, the place where Lot was banished, and drank the water and it was bitter.
3. (noun) irritation, annoyance, frustration, itchiness.
Mā te pani ki te pēkena houra e heke ai te pupuhi, e iti iho ai anō hoki te mangeo (HJ 2015:73). / Applying baking soda will reduce the swelling, and also there will be less itchiness.