這個拼法底下其實是2個不同的字，意思沒有關係， 只是長得一樣。下面分開列出來。跳到 內襯；襯袋 · 客輪；郵輪
For this group you can picture the layer that sits inside something else. A bin has a bag in it. A cake tin has a paper cup in it. A coat has a soft layer buttoned into it. A record case has a folded sheet of paper tucked into it. In every one of those pictures the outside thing is the container, the inside layer is thin and shaped to fit, and it can be pulled out and replaced when it is dirty, worn, or simply finished with. Whatever we call the container, the liner is the layer we put in.
Wiktionary records this group as line (verb) + -er: the verb line means to put a layer inside something, so a liner is the thing that does that.
Wiktionary 把這一支記成 line（動詞）+ -er。動詞 line 指「在裡面鋪一層」，加上 -er 就成了「鋪在裡面的那個東西」，剛好對得上內襯和唱片內頁兩個用法。
Wiktionary (via kaikki) entry 'liner', etymology 1: 'From line (verb) + -er.' — source_ref kaikki:3f6f69a190036ae4:1001280754
From the picture
鋪在裡面的那一層
這一家的兩個意思都是同一個動作的結果：有人把一層東西鋪進容器裡。差別只在容器是垃圾桶還是唱片盒，鋪進去的是塑膠袋還是印了字的紙。
noun · B2
A piece of thin material — plastic, paper or cloth — that is put inside a bin, bag, box, tin or piece of clothing, usually to keep the inside clean or to protect it. You can normally take it out and put in a new one.
內襯；襯袋
noun · C1
The printed sheet or small booklet that comes inside the case of a record, CD or tape, carrying song words, photographs and information about the music. It is used most often in the phrase liner notes.
唱片內頁（說明）
A second word, same spelling
For this group the picture is a line. A shipping company draws a route on a map and runs the same ships along it, week after week, and the ship that keeps to that line is a liner. A batter hits a ball so flat and fast that it travels almost along a straight line, and that hit is a liner too. Someone draws a fine dark line along the edge of an , and the pen that draws it is a liner. The line may be a route, a flight path, or a stroke of make-up, but something is following a line in every case.
Wiktionary records a second, separate route for this group: line (noun) + -er — the noun line meaning a route or a row, not a lining.
Wiktionary 把這一支另外記成 line（名詞）+ -er，跟「內襯」那一支來源不同。這裡的 line 是航線、路線、一排的意思，不是「鋪一層」。眼線那個意思來源沒有直接說明歸在哪一支，這裡是依畫面歸類的，屬於教學上的整理，不是歷史主張。
Wiktionary (via kaikki) entry 'liner', etymology 2: 'From line (noun) + -er (relational suffix) or -er (measurement suffix) (sense 5).' — source_ref kaikki:3f6f69a190036ae4:1001300412
From the picture
跑固定航線的大船
把那條線畫在海圖上，沿著它跑的船就是這一家：路線固定、時間固定，所以才會有這個名字。
noun · B2
A large ship that carries passengers, especially one that sails a fixed route between ports or takes people on a long holiday at sea.
客輪；郵輪
一條線：畫出來的，或打出去的
這一家不走海上，改把「線」放到別的地方：一條畫在眼皮上的線，一條球飛出去的線。都是沿著線走，只是這條線短得多。
noun · B2
Eyeliner: a pencil, pen or liquid make-up used to draw a line close to the edge of the eyelids. In relaxed speech people often drop the eye- and just say liner.
眼線（筆）
noun · B2
In baseball, a ball that the batter hits hard and low, so that it travels almost in a straight line and stays close to the ground instead of going high into the air. The longer name is a line drive.
平飛球（強勁的直線安打球）