Wiktionary
n. (context phonetics English) Any vowel sound produced in the front of the mouth. Examples: "a" in “man” and "e" in “gel”
Wikipedia
A front vowel is any in a class of vowel sound used in some spoken languages, its defining characteristic being that the tongue is positioned as far in front as possible in the mouth without creating a constriction that would make it a consonant. Front vowels are sometimes also called bright vowels because they are perceived as sounding brighter than the back vowels.
Near-front vowels are essentially a type of front vowels; no language is known to contrast front and near-front vowels based on backness alone.
Rounded front vowels are typically centralized, that is, near-front in their articulation. This is one reason they are written to the right of unrounded front vowels in the IPA vowel chart.