An aide is an assistant or helper. The word always refers to a person. Aid is a noun referring to (1) assistance, or (2) something that assists (e.g., a hearing aid or a visual aid), and it’s also a verb meaning to assist. Some dictionaries list aid as a variant of aide, but the words are generally kept separate in edited writing.
Both words derive from closely related French sources, but they entered English at different times. Aid came to English in the 15th century (and had several spellings in early use) and has borne a variety of meanings over the centuries.1 Aide entered English several centuries later, possibly as a shortened form of aide-de-camp, which refers to a military officer who assists a superior.2
A senior aide to the Archbishop of Canterbury has ridiculed the Bishop of London over his handling of the St Paul’s protest. [Evening Standard]
These early physical therapists, known as reconstruction aides, received orders from physicians but did not evaluate patients. [Wellness and Physical Therapy, Sharon Fair]
South Korean officials said Tuesday the country has approved $6.94 million in aid to be sent to its neighbor. [CNN]
Prospective hearing aid users were allowed to adjust their aids for comfort during all of these listening experiences. [Aural Rehabilitation, Raymond H. Hull]
Murphy and Falchuk are aided by a strong cast including a scene-stealing Jessica Lange as the very steely magnolia next door. [Independent]