人走之后留在空气里的那道香——本义是船的尾流：身体已经过去，痕迹还拖在后面。 The scent a person leaves hanging in the air — literally a ship's wake: the body gone by, the trace still trailing.
The scent a person leaves hanging in the air — literally a ship's wake: the body gone by, the trace still trailing. 人走之后留在空气里的那道香——本义是船的尾流：身体已经过去，痕迹还拖在后面。
词源etymology
法语 siller（破浪前行）→ sillage：船犁开水面留下的 V 字尾流。 猎人先把它借上岸——兽已远去，气味的沟还刻在黎明的空气里，猎犬读得出； 调香师再把它借进香水行——人离开房间，香还替他在场。 一个词转租三次，一次比一次轻。
French siller (to cleave forward through water) → sillage: the V a ship plows into the sea. Hunters borrowed it ashore first — the stag long gone, its scent still furrowed into the dawn air, legible to hounds; then the perfumers took the lease — the person leaves the room, the scent holds their seat. One word sublet three times, lighter at every move.
背景the story
在调香行话里它是正式的评香维度：一支香水「留尾」几何—— 贴肤还是满堂，是 sillage 大小。但它真正命名的是一件更普遍的事： 离场之后的在场。人不在了，还没走干净—— 这件事水上叫尾流，林中叫踪，人间叫余香。
In perfumery’s shop-talk it is a formal axis of judgment: how much wake a fragrance leaves — skin-close or room-filling — is its sillage. But what it truly names is more general: presence after exit. Gone, but not entirely gone — on water called a wake, in the woods a trail, among people a lingering scent.
中文里的邻居neighbors in chinese
「余香」正中靶心——「余」字一族分工严明：余音管声，余香管味，余韵管一切的抽象。 「暗香浮动」更美，可林逋写的是在场的暗香；sillage 专管人已不在的那种。 切法也不同：中文的「余」以时间下刀——还没散； sillage 以空间下刀——拖在身后。一个是残留，一个是尾迹。
余香 — “remaining fragrance” — hits center: the 余-family divides labor strictly (余音 for sound, 余香 for scent, 余韵 for the abstract of both). 暗香浮动 is lovelier still, but Lin Bu’s drifting scent is present; sillage handles the kind whose owner has left. The cut differs too: the Chinese 余 cuts by time — not yet dispersed; sillage cuts by space — trailing behind. One is residue, the other a wake.
She was three rooms away by then, but her sillage was still conducting the interview. 自拟例句 our own example, not a quotation Good sillage is a slow exit; great sillage is an alibi. 自拟例句 our own example, not a quotation 法语真词（Larousse 在录）；英文香评圈通行，可不斜体，圈外首次出现给一句解释。 写人物的进场退场，它是现成的摄影机位。
A real French word (in the Larousse); standard in English perfume writing without italics — gloss it once for readers outside the trade. For entrances and exits in prose, it is a camera position kept ready.