expression / noun:

• low spirits; depressed heart

noun:

• gatekeeper (in suicide prevention); person who prevents others from committing suicide (by noticing they are depressed and talking to them about it, etc.)
• gatekeeper (in media, networking, etc.)

godan ~る verb / intransitive verb:

• to rot; to go bad; to decay; to spoil; to fester; to decompose; to turn sour (e.g. milk)
• to corrode; to weather; to crumble
• to become useless; to blunt; to weaken (from lack of practice)
• to become depraved; to be degenerate; to be morally bankrupt; to be corrupt
• to be depressed; to be dispirited; to feel discouraged; to feel down ➜ 気が腐る【きがくさる】

auxiliary verb / godan ~る verb:

• to have the audacity to; to be bastard enough to - after the -masu stem of a verb; indicates scorn or disdain for another's action - usually written using kana alone - Kansai dialect ➜ やがる

godan ~る verb / intransitive verb:

• to lose a bet - archaism
• to be drenched; to become sopping wet - archaism

ichidan verb / intransitive verb:

• to wither; to wilt; to droop; to fade - esp. 萎れる, 凋れる
• to be dejected; to be disheartened; to be depressed; to be crestfallen - esp. 萎れる, 悄れる

adverb / ~と adverb / ~する noun:

• hazy; misty; foggy; murky; fuzzy - onomatopoeia

adverb / ~と adverb / ~する noun / noun:

• hazy feeling; uncertain feeling; feeling gloomy; feeling depressed; pent-up feelings; ill feeling - onomatopoeia

godan ~る verb / intransitive verb:

• to become damp; to become moist; to become wet
• to lack energy; to be in a slump; to be in low spirits; to feel depressed ［しめる］ - often as 湿って or 湿った

godan ~む verb / intransitive verb:

• to sink; to go under; to submerge
• to go down (e.g. sun); to set; to descend
• to feel depressed

godan ~ぐ verb / transitive:

• to stop up; to close up; to block (up); to plug up; to shut up; to cover (ears, eyes, etc.); to close (eyes, mouth)
• to stand in the way; to obstruct
• to occupy; to fill up; to take up
• to perform one's role; to do one's duty

godan ~ぐ verb / intransitive verb:

• to feel depressed; to be in low spirits; to mope ➜ 鬱ぐ【ふさぐ】