1
the supernatant
作名词时通常用定冠词，指离心或沉淀后上层的清液。
After centrifugation, the supernatant was carefully collected.
离心后，小心收集上层清液。
上清液；上层清液
先理解核心含义，再看它在真实句子里的用法。
上清液；上层清液
the clear liquid that lies above a sediment or precipitate
After centrifugation, the supernatant was carefully collected.
离心后，小心收集上层清液。
沉淀物或析出物上方的液体
The liquid that lies above a sediment or precipitate.
漂浮在液体表面的物质
Material that floats on the surface of a liquid.
After the mixture was left to settle, the clear supernatant was poured off.
混合物静置后，将清澈的上清液倒出。
The lab stored the supernatants in a freezer for later analysis.
实验室将上清液冷冻保存，以备后续分析。
The supernatant liquid was collected without disturbing the sediment.
收集上层液体时未扰动沉淀。
作名词时通常用定冠词，指离心或沉淀后上层的清液。
After centrifugation, the supernatant was carefully collected.
离心后，小心收集上层清液。
作形容词修饰名词，常与 liquid、fluid、layer 等搭配。
The supernatant liquid was clear and colorless.
上层清液清澈且无色。
需要指明上清液来源时，用 of 引出。
The supernatant of the cell lysate was used for further analysis.
细胞裂解物的上清液用于进一步分析。
Not this
The supernatant from the samples were transferred to a new tube.
Use this
The supernatant from the samples was transferred to a new tube.
句子的主语是 single noun 'supernatant'（上清液），尽管后面有定语 'from the samples'，动词仍须与主语中心词保持一致，用单数 was。中文没有主谓一致，学习者因看到 samples 而误用复数 were。
Not this
After standing, the clear liquid will supernatant at the top of the tube.
Use this
After standing, the clear liquid will form a supernatant at the top of the tube.
'supernatant' 是名词或形容词，不是动词，不能直接作谓语。应添加动词 form，并把 supernatant 用作宾语，表示“形成上层清液”。中文的词性区分较灵活，学习者容易把名词/形容词直接当动词用。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
培养上清液
The culture supernatant was collected after centrifugation.
离心后收集培养上清液。
无细胞上清液
Cells were removed, and the cell-free supernatant was stored at -80°C.
去除细胞后，将无细胞上清液储存在-80°C。
上清液
The supernatant fluid should be clear and free of debris.
上清液应清澈，不含残渣。
弃去上清液
After centrifugation, carefully discard the supernatant without disturbing the pellet.
离心后小心弃去上清液，不要扰动沉淀。
收集上清液
Collect the supernatant and transfer it to a new tube.
收集上清液并将其转移到新管中。
Use supernatant naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
“super”在上 + “natant”漂浮 → 漂浮在上层的清液：离心后沉淀在下，上清液在上。
语域：formal 常见场景：实验室、生物化学、医学检验 supernatant 是正式、专业的科技用词，通常出现在实验室报告、科研论文和医学检验中，日常口语很少使用。作名词时指上层清液，作形容词时指上层的；多用于书面和技术性说明。
真正押韵的是读音中以 /-eɪtənt/ 结尾的词，如 natant（/ˈneɪtənt/）和 latent（/ˈleɪtənt/）；supernatant 的重音在 -nat-，所以与它们同韵。tenant、important、consultant 虽然拼写有相似的 -tant/-ant 结尾，但读 /-ənt/，不押韵；super 只是开头拼写和读音相同。
Dictionary facts from ECDICT, WIKTIONARY.