Definition:  There are three slightly different ways to define the word “vague.” In English, vague can be defined as the following:

1. Not clearly defined or understood.
2. Not clearly expressed or stated in indefinite terms.
3. Not clearly visible, not clearly felt, or not clearly sensed.

Etymology: Borrowed from Middle French, the word vague originally derives from the Latin root word vagus. In Latin, vagus is defined literally as wandering, rambling, or strolling. 

Figuratively, vagus could mean doubtful, wavering, uncertain, or inconsistent. In addition to “vague,” other words as vagrant, vagabond, and divagation also come from the same root word, vagus.

The Swedish word vag and Italian word vago also have the same etymology as vague.

In a Sentence

The students were quite confused about their latest assignment because the teacher’s instructions were far too vague.

Due to the downpour of heavy rain and wind, I could only see a vague outline of the house in front of me.

Synonyms 

Indistinct, Indefinite, Unclear, Hazy

Antonyms 

Clear, Precise, Firm, Sharpness