imperceptible

Borrowed from Middle French imperceptible, from Medieval Latin imperceptibilis

imperceptible (comparative more imperceptible, superlative most imperceptible)

1. not perceptible, not detectable, too small in magnitude to be observed
   • 1986, Derek Parfit, Reasons and Persons, OUP Oxford (→ISBN), page 75:

     Very small benefits may be imperceptible. And it is plausible to claim that an 'imperceptible benefit' is not a benefit.

   We all missed the imperceptible shake of his head as he tried to warn us without being seen.

   Synonyms: imperceivable, undistinguishable, unperceivable

   Antonyms: detectable, perceptible

From Medieval Latin imperceptibilis, equivalent to im- +‎ perceptible.

• (Balearic) IPA^(key): /im.pəɾ.səpˈti.blə/
• (Central) IPA^(key): /im.pər.səpˈti.blə/
• (Valencian) IPA^(key): /im.peɾ.sepˈti.ble/

imperceptible (masculine and feminine plural imperceptibles)

1. imperceptible

From the Medieval Latin imperceptibilis.

• IPA^(key): /ɛ̃.pɛʁ.sɛp.tibl/

imperceptible (plural imperceptibles)

1. imperceptible

• “imperceptible” in le Trésor de la langue française informatisé (The Digitized Treasury of the French Language).

From Medieval Latin imperceptibilis, equivalent to im- +‎ perceptible.

• (Castilian) IPA^(key): /impeɾθebˈtible/, [ĩmpeɾθeβˈt̪iβle]
• (Latin America) IPA^(key): /impersebˈtible/, [ĩmperseβˈt̪iβle]

imperceptible (plural imperceptibles)

1. imperceptible