Plural of “echo”

The plural of echo is echoes.

Why

"Echo" comes from Greek "ekho," sound, by way of the myth of Echo, the nymph condemned to only repeat the last words spoken to her. It entered English in the 14th century, early enough to be treated as a fully naturalized English word rather than a foreign import kept at arm's length, and English nouns ending in a consonant plus -o that assimilated early tend to take the fuller -es plural rather than a bare -s.

That -es pattern groups "echo" with a small cluster of similarly old, similarly assimilated -o nouns — "hero," "potato," "tomato" — all borrowed centuries ago and treated by English spelling conventions as needing the extra vowel before the plural -s, the same reasoning that gives "tomato" its "tomatoes" rather than "tomatos."

Usage note

"Echoes" is standard in every register, from acoustics and physics to the figurative sense of echoes of the past. There's no accepted competing plural the way there is for "volcano" or "cargo"; "echos" is simply considered a misspelling.

The myth of Echo, as told by the Roman poet Ovid, ties her curse directly to the goddess Juno, who punished her for distracting attention with endless chatter while Jupiter pursued other nymphs, condemning Echo to only ever repeat what others had just said. "Echo" also names the internationally standardized phonetic alphabet code word for the letter E, an entirely modern coinage unrelated to either the acoustic phenomenon or the mythological figure.

Common real mistakes

Because so many -o nouns these days ("photo," "piano," "video") take a plain -s, writers sometimes drop the -e out of habit and write "echos." It's an understandable slip given how inconsistent this whole word class is, but it isn't accepted in standard spelling. Writers should also avoid confusing the acoustic "echo" with "reverberation," a related but technically distinct audio phenomenon involving many overlapping reflections rather than a single distinct repeated sound.

The wider pattern

"Echo" sits with "hero," "potato," "tomato," and "veto" in the older, fully assimilated layer of English -o nouns that take -es, a pattern that contrasts sharply with the many newer or more obviously foreign -o nouns — "piano," "photo," "studio" — that simply add -s, making this entire word class one of the least predictable corners of English spelling.

Examples

• The canyon walls sent echoes bouncing for miles.
• Faint echoes of the old factory whistle still lingered in memory.
• Sonar uses sound echoes to map the ocean floor.
• The empty hall was full of echoes with every footstep.
• Echoes of the scandal followed him for years.
• Scientists study echoes to measure the depth of caves.
• The singer's voice produced strange echoes in the stone chapel.
• Two distinct echoes returned from the far side of the valley.
• Political echoes of the earlier crisis were unmistakable.
• The recording captured faint echoes from the surrounding hills.
• The cave produced overlapping echoes that confused the hikers.
• Engineers designed the concert hall to minimize unwanted echoes.
• Hikers shouted into the canyon just to hear the echoes.
• The stadium's design amplified echoes during the final match.
• The old mine shaft produced eerie echoes when explored.
• Radar echoes revealed the storm's exact position.
• The choir's final note lingered in echoes throughout the hall.
• Explorers noted strange echoes deep within the limestone caves.
• The valley returned faint echoes long after the shout ended.
• Engineers tested the room for unwanted echoes before recording.
• The old well produced a startling echo when tapped.
• The tunnel amplified even the softest echoes.
• She recorded the echoes for the sound design project.
• Bats use echoes to navigate through total darkness.
• The empty warehouse amplified every footstep into an echo.
• Sound designers layered echoes to create the eerie atmosphere.