尽 (jǐn) + position word: the very… (farthest)
【高06】副词 / adverbs (程度)
Tone colorsā tone 1á tone 2ǎ tone 3à tone 4a neutral
尽 (jǐn) + position word: before a word of place, 尽 picks out the extreme point, "right at the end, the very front, the very back": 坐在尽前头的是我女朋友; 尽北边有一个空位，您可以考虑这个位置. 尽前头 is much like 最前面, and 尽北边 like 最北边.
It is a spoken use, with a rather northern flavour, and it is built only with a position word (前头, 后头, 里头, 上头, 东边, 北边…). It is not a degree adverb like 很 or 最: you do not say 尽漂亮, but 最漂亮 or 很漂亮.
Watch the reading: here 尽 is jǐn (3rd tone), as in 尽管 (hsk3-g49), 尽量 and 尽快, which are words of their own ("although", "as far as possible", "as soon as possible"). In 尽力 (jìnlì, "do one's best") and 尽头 (jìntóu, "the end") it is read jìn (4th tone).
Examples
坐在尽前头的是我女朋友。
Zuò zài jǐn qiántou de shì wǒ nǚpéngyou.The one sitting right at the front is my girlfriend.
尽北边有一个空位，您可以考虑这个位置。
Jǐn běibian yǒu yí ge kòngwèi, nín kěyǐ kǎolǜ zhège wèizhì.There is a free seat at the far north end; you might consider that one.
走廊尽里头的那间屋子，就是我们的实验室。
Zǒuláng jǐn lǐtou de nà jiān wūzi, jiùshì wǒmen de shíyànshì.The room at the very end of the corridor is our lab.
请把车停在尽后头，不要堵住前面的路。
Qǐng bǎ chē tíng zài jǐn hòutou, bú yào dǔzhù qiánmiàn de lù.Please park right at the back, and don't block the road ahead.
图上尽北边的红点，是大雁夏天繁殖的地方。
Tú shang jǐn běibian de hóngdiǎn, shì dàyàn xiàtiān fánzhí de dìfang.The red point at the far north of the map is where the geese breed in summer.
Common mistakes
✗ 她尽漂亮。 → ✓ 她最漂亮。 (尽 does not intensify an adjective: it needs a position word).
✗ 尽那个房间 → ✓ 尽里头的那个房间 (a bare place noun is not enough: 尽 goes before 前头, 里头, 北边…).
✗ 尽前头 read as jìn qiántou → ✓ jǐn qiántou (here 尽 is 3rd tone).