wither

it seems to me that the history of corporate acquisitions is littered with takeovers in which the shareholders may have profited, but the corporation's life and creativity withered.

mycelium

The vegetative part of a fungus, consisting of a mass of branching, threadlike hyphae.
hypha (pl hyphae): 菌糸

tenacious

1. Holding or tending to hold persistently to something, such as a point of view. See synonyms at strong.
2. Holding together firmly; cohesive: a tenacious material.

get under (one's) skin

1. To irritate or stimulate; provoke.
2. To become an obsession.

scrounge

v.t. せびり取る.
v.i. あちこちあさる.

have A to show for B

Bに対する成果としてAを得ている

A wise dog doesn't let his fleas bother him.

という諺があるんだな。