名詞 bottom:

1. the lower side of anything
   同義詞：underside, undersurface
2. the lowest part of anything
3. the fleshy part of the human body that you sit on
   同義詞：buttocks, nates, arse, butt, backside, bum, buns, can, fundament, hindquarters, hind end, keister, posterior, prat, rear, rear end, rump, stern, seat, tail, tail end, tooshie, tush, behind, derriere, fanny, ass
4. the second half of an inning; while the home team is at bat
   同義詞：bottom of the inning
5. a depression forming the ground under a body of water
   同義詞：bed
6. low-lying alluvial land near a river
   同義詞：bottomland
7. a cargo ship
   同義詞：freighter, merchantman, merchant ship

動詞 bottom:

1. provide with a bottom or a seat
2. strike the ground, as with a ship's bottom
3. come to understand
   同義詞：penetrate, fathom

形容詞 bottom:

1. situated at the bottom or lowest position
2. the lowest rank

1. She started at the bottom and worked her way up to become manager of the company.
   她從最低的位置干起，通過努力終於當(dāng)上了公司的經(jīng)理。
2. He was always bottom of the class in maths.
   他的數(shù)學(xué)成績在班上總是墊底。
3. They sent the enemy ship to the bottom of the sea.
   他們把敵艦擊沉。

bot.tom

n.Abbr. bot.（名詞）縮寫 bot.
The deepest or lowest part:
底部：最深或最低的地方：
例句：
the bottom of a well; the bottom of the page.
井底；書頁的底部

The underside:
下側(cè)，底面：
例句：
scraped the bottom of the car on a rock.
巖石擦壞了汽車底盤

The supporting part; the base.
基礎(chǔ)；基底
The far end or part:
遠(yuǎn)端，遠(yuǎn)處：
例句：
at the bottom of the bed.
在床的盡頭

The last place, as on a list.
最后部分：名單的最末處
The lowest or least favorable position:
基層職務(wù)：最低賤和不令人滿意的職務(wù)：
例句：
started at the bottom of the corporate hierarchy.
從公司的最基層干起

The basic underlying quality; the source:
起源：根本，基礎(chǔ)；來源：
例句：
Let`s get to the bottom of the problem.
讓我們回到問題的源頭

The solid surface under a body of water.
水底：水下的固體表面
Often bottoms Low-lying alluvial land adjacent to a river.Also called bottomland
常作 bottoms 低洼地，灘地：與河流鄰接的低洼沖積地帶也作 bottomland

Nautical The part of a ship`s hull below the water line.
【航海】 船底：在水線下的船身部分
A ship; a boat:
船；小艇：
例句：
.English merchants did much of their overseas trade in foreign bottoms.(G.M. Trevelyan)
.英國商人在外國船只中進(jìn)行大量海外貿(mào)易.(G.M.特里維廉)

Often bottoms The trousers or short pants of pajamas.
常作 bottoms 睡褲：長褲或短睡褲
Informal The buttocks.
【非正式用語】 臀部
The seat of a chair.
椅子的座位
Baseball The second or last half of an inning.
【棒球】 下半場：一局中的第二或最后半場
Staying power; stamina. Used of a horse.
耐力；體力。用于指馬的耐力
n.attributive.（定語名詞）
Often used to modify another noun:
常用于修飾另一名詞：
例句：
a bottom drawer; the bottom stair.
底層抽屜；底層樓梯

v.（動詞）
bot.tomed,bot.tom.ing,bot.toms
v.tr.（及物動詞）
To provide with an underside.
給…裝底：用內(nèi)側(cè)裝備
To provide with a foundation.
建立…的基礎(chǔ)
To get to the bottom of; fathom.
探測：到達(dá)…的底部；探測
v.intr.（不及物動詞）
To be or become based or grounded.
做準(zhǔn)備：有底基或基礎(chǔ)的
To rest on or touch the bottom.
觸底：?？吭诨蚪佑|底部

<常用詞組>bottom out
To descend to the lowest point possible, after which only a rise may occur:
跌到谷底：跌到可能的最底點(diǎn)，在其后只有一個(gè)回升會發(fā)生：
例句：
Sales of personal computers have bottomed out.
個(gè)人電腦的銷售跌到了最底點(diǎn)

<習(xí)慣用語>at bottom
Basically.
根本上
來源：
Middle English botme
中古英語 botme
from Old English botm
源自 古英語 botm

【引伸】
bot.tomer
n.（名詞）