indefinable

He had that indefinable, invisible glow that changes the atmosphere and draws people in, like a sub-lethal dose of radiation.

They introduced me to a vibrant mix of people - some became short-term flings, others full-blown relationships, and then there were the other indefinable in-betweens.

It expresses a general anxiety the prompt of which is indefinable, a nagging sense that has no singularly compelling explanation.

When it’s completely indefinable, it exists as a cloud.

A recent New Yorker profile of Jeremy Strong seemed determined to find eccentricity in the actor’s dedication to craft, just as so many people with public platforms voiced their often indefinable irritation with Hathaway’s.