( ( Pathogen ( ( ( A ( disease ( causing agent ) ) ) , ) ( especially ( a ( virus ( , ( ( bacterium or ) fungus ) ) ) ) ) ) ) . )
(ROOT (S (VP (VB Pathogen) (NP (NP (DT A) (NN disease) (VBG causing) (NN agent)) (, ,) (NP (RB especially) (DT a) (NN virus) (, ,) (NN bacterium) (CC or) (NN fungus)))) (. .)))
Pathogen A disease causing agent, especially a virus, bacterium or fungus.
(ROOT (S (NP (NP (NNS Bacteria)) (, ,) (NP (NNS viruses)) (, ,) (NP (NNS fungi)) (, ,) (CC and) (NP (NN protozoa))) (VP (VBP are) (NP (NP (NNS examples)) (PP (IN of) (NP (NP (DT a) (NN pathogen)) (, ,) (NP (NP (DT the) (NN term)) (PP (IN for) (NP (DT a) (JJ disease-causing) (NN microorganism)))))))) (. .)))