だらけ details

Examples

covered in N; full of N — an unwelcome or messy quality is everywhere, in visible quantity

公園こうえんから帰かえってきた子供こどもたち、泥どろだらけだったよ。

kouen kara kaette kita kodomotachi, dorodarake datta yo.

The kids came home from the park covered in mud, you know. casual

提出ていしゅつする前まえに確認かくにんしたのに、この原稿げんこうはまだ間違まちがいだらけです。

teishutsu suru mae ni kakunin shita noni, kono genkou wa mada machigaidarake desu.

I checked it before submitting, but this manuscript is still full of mistakes. neutral

傷きずだらけの車くるまで駐車場ちゅうしゃじょうに入はいってきた。

kizudarake no kuruma de chuushajou ni haitte kita.

A car covered in scratches pulled into the parking lot. neutral

Adnominal form takes の, not な: 間違まちがいだらけの原稿げんこう, never
×間違いだらけな原稿 — だらけ behaves like a noun here, not a な-adjective.

がち
だらけ reports a QUANTITY of something negative saturating a state right now — mass or countable alike (泥[どろ]だらけ "covered in mud", 間違[まちが]いだらけ "full of mistakes"), while がち reports a recurring BEHAVIORAL TENDENCY over time (病気[びょうき]がち "prone to getting sick") — one is a snapshot of built-up quantity, the other a pattern of frequency.