may be regional or slightly old-fashioned but certainly not wrong - even if two people in CP's office don't recognise the term.
Chambers 21st Century Dictionary
adj (angrier, angriest)
1 feeling or showing annoyance, resentment, wrath, disapproval, etc.
2 irritable, cross, ill-tempered, etc, an angry expression. 3 said of a wound, rash, etc: red and sore.
4 dark and stormy http://www.chambersharrap.co.uk/chambers/feat...
adj., -gri·er, -gri·est.
1.Feeling or showing anger; incensed or enraged: angry at a rude neighbor; angry with a salesclerk.
2.Indicative of or resulting from anger: an angry silence.
3. Having a menacing aspect; threatening: angry clouds on the horizon.4. Chiefly New England & Midland U.S. Inflamed and painful: an angry sore.http://www.answers.com/angry&r=67
Medical and Pharmaceutical Dictionary Werner E. Bunjes, 1981 Georg Thieme Verlag:
zornig, aufgebract(at a th., with s.o. über, auf) med.
There is already an entry in LEO for "inflamed - entzündet" - which is, of course, also correct:Siehe Wörterbuch: inflamed
perhaps you just need to buy a bigger dictionary ;-)