Plural of “antenna”

The plural of antenna is antennas (some dictionaries also accept antennae).

Why

"Antenna" is Latin for "sail yard" (the pole that held up a ship's sail), and it originally took the Latin first-declension -a/-ae plural, giving "antennae" — but English split the word's plural cleanly by meaning once it developed two distinct senses in the 19th and 20th centuries.

"Antennae" is the standard, essentially unchallenged plural in biology, referring to the paired sensory feelers on insects and crustaceans, while "antennas" is the standard plural for the technological sense, referring to radio, television, or communication devices — a genuine, well-established split by field rather than a matter of formality or personal preference. Entomologists further distinguish antennae by shape and function across insect orders — moths' feathery antennae detect pheromones over long distances, while many beetles' antennae are simpler and used mainly for close-range touch and taste — none of which changes the grammar, but all of which explains why entomologists reach for the word so constantly in precise, specialized writing.

Usage note

Say "antennae" about a car radio, or "antennas" about a butterfly's feelers, and an engineer or an entomologist will each quietly notice the mismatch, even though general dictionaries tend to list both plurals for both meanings without comment; among specialists themselves, though, the subject-matter split is observed so consistently that it behaves almost like a hard rule rather than a mere tendency.

The figurative use of "antennae" ("she has great antennae for spotting talent," meaning sharp instincts or sensitivity) borrows specifically from the biological sense rather than the technological one, extending the insect-feeler image metaphorically into everyday language about perceptiveness and social awareness. Older American slang used "antennae" informally and figuratively for a person's general perceptiveness well before the phrase became more standardized as "good antennae for something," a usage that has stayed remarkably stable in form despite drifting quite far from its original insect-biology meaning. Wildlife photographers specializing in insects often note that antennae position and movement can reveal a great deal about an insect's alertness or intent, a detail purely about behavior rather than about the word's grammar.

Common real mistakes

The most common real mix-up is using the wrong plural for the wrong sense — describing a moth's "antennas" or a car's "antennae" — a subtle error that doesn't affect comprehension but does mark a writer as unfamiliar with the field-specific convention that has developed around this particular word. It's also a mistake to treat "antennas" as a casual shortcut — it's the correct, standard technical term for radio and communication equipment in its own right, not a looser alternative to the biological "antennae."

The wider pattern

Grammatically, "antenna" sits in the same Latin first-declension -a/-ae group as "formula/formulae," "larva/larvae," and "vertebra/vertebrae" — though of that whole set, it stands out as the one whose two plurals diverged by subject matter rather than one form simply winning out over time.

Examples

• The moth's antennae twitched as it sensed the light.
• Several rooftop antennas were damaged in the storm.
• Insects use their antennae to detect chemical signals in the air.
• The old television relied on two adjustable antennas for reception.
• Both antennae helped the ant navigate back to the colony.
• Engineers installed new antennas to improve cell phone coverage.
• The beetle's antennae were noticeably longer than the female's.
• Radio antennas dotted the hillside above the small town.
• Scientists studied how antennae help insects locate food sources.
• The car's antennas were retractable for easier car washes.
• The satellite dish and older rooftop antennas shared the same mounting bracket.
• The insect's antennae brushed against the leaf before it took flight.
• The ladybug's short antennae were barely visible without magnification.
• Old cars often had a single manual antenna mounted on the fender.
• The technician replaced two broken antennas on top of the tower.
• The astronomer adjusted the radio antenna to capture a clearer signal.