1. In an imperceptible manner or to an imperceptible degree
   - imperceptibly

See also: unnoticeable

• ICU
• icy
• icy pole
• id
• Id al-Adha
• Id al-Fitr
• ID card
• id est
• IDA
• Ida M. Tarbell
• Ida Minerva Tarbell
• Ida Tarbell
• Idaho
• Idaho Falls
• Idahoan
• IDDM
• idea
• ideal
• ideal gas
• ideal solid
• idealisation
• idealise
• idealised
• idealism
• idealist