The closet is full of junk.
This shop sells nothing but rubbish.
ガラクタ is a native Japanese word for worthless odds and ends with a strong clutter nuance, while ジャンク is a modern loanword often used in compounds like ジャンクフード.
ガラクタ is a general word for worthless junk of any kind, while ポンコツ specifically implies something that used to work (like a car or machine) and has broken down.
がらくた is the everyday word for useless junk or odds and ends around the house, whereas 瓦礫 specifically means rubble left from destruction.
ガラクタ is a casual, often disparaging word for worthless junk, while 不用品 is a neutral term for items that are simply no longer needed.
がらくた means worthless junk, the opposite of 宝, which is something precious and valued.
Standard kana spelling; the word is usually written in kana.
Katakana spelling, sometimes used for emphasis or in informal writing.
Ateji spelling; rarely used.
Ateji spelling; rarely used.
The origin is uncertain. It may be related to がら (worthless) and くた (rubbish), but the exact derivation is unclear.