かいこう
Meanings
Noun
Verb (する)
1. opening; aperture (e.g. camera)
2. opening one's mouth; beginning to speak
Pre-noun adjective
3. open; broad
Pitch accent
いこう
Used in vocabulary (5 in total)
at the very beginning of one's speech; the first thing (one) says after opening the mouth
numerical aperture (in photography)