momentaneous

9.9

Lasting for a very short time

adjective
/ˌmoʊməˈteɪniəs/

Archaic

: momentáneo

The painter captured a momentaneous expression of surprise on the child's face.

Examples

She experienced a momentaneous lapse of concentration.
Their happiness was momentaneous, vanishing almost as soon as it appeared.
Such momentaneous changes in weather are difficult to predict.
The joy was momentaneous but unforgettable.
The happiness he felt was momentaneous, fading away in an instant.
She had a momentaneous doubt about her decision, but it quickly passed.
His momentaneous excitement was evident when he heard the good news.

Synonyms

fleeting

vsmomentaneous

66 6.3

Lasting only a short time

emphasizes short lasting rather than rapid motion

momentary

vsmomentaneous

44 4.8

Lasting only a very short time

is the same meaning but used as an alternative form

transient

vsmomentaneous

38 7.0

Lasting only a short time and not permanent

focuses on very brief duration rather than longer temporary status

instantaneous

vsmomentaneous

35 5.1

Happening right away without any delay

refers to short length of time rather than immediate occurrence

fugitive

vsmomentaneous

23 7.4

Lasting only a short time and ending quickly

describes short duration plainly rather than implying temporary existence

ephemeral

vsmomentaneous

17 8.6

Lasting only a very short time

focuses on brief duration rather than speed or suddenness

transitory

vsmomentaneous

11 6.8

Lasting only a short time

means short lasting rather than implying permanent change

Antonyms

perpetual

93 5.8

Lasting for a very long time without stopping

enduring

1 4.2

Continuing for a long time without fading

How Brief

instantaneous

35 5.1

momentaneous

Archaic

9.9

transient

38 7.0

temporary

557 3.0

lasting

38 3.1

Surface Forms

momentaneous positive

Morphology

momentaneous = moment (semi-transparent) = moment + aneous

The word is clearly based on 'moment', but the Latinate suffix '-aneous' is not very productive or obvious for most learners.

Etymology

The word momentaneous comes from the same root as moment, which means 'a very short time'. So something momentaneous lasts only a single moment and is therefore very brief or fleeting.