Onslow

Boys' name

From Middle English Ondeslow; literal meaning unconfirmed

Onslow has been given to 7 babies in the U.S. since 1917. It was used fewer than 5 times in 2025, so it doesn't appear in the latest year's list — today it's a genuinely uncommon pick. Its peak year was 1917, with 7 recorded.

Babies named Onslow, 1917

1 in 287,000

Onslow over time, 1880–2025

Boys

Based on births in the U.S. Babies given the name each year. Hover the chart — or focus it and use the arrow keys — for any year. Gaps mean the name was given fewer than 5 times that year; these counts are unpublished.

Onslow: meaning, origin, and history

From Middle English Ondeslow; literal meaning unconfirmed

Germanic languages

What Onslow means

Onslow is a given name.

Dictionary etymologyReferences, data & attribution

From Middle English Ondeslow, Ondeslowe, Ondeslawe, Andeslawe, Hundeslawe, Hundreslawe, Andreslawe, from Old English *Andrǣd (a male given name) + hlāw, hlǣw (“hill”) (literally, "Ander's hill").

Excerpt from Wiktionary: Onslow (English) · CC BY-SA 4.0

Wiktionary material is available under CC BY-SA 4.0.

Origin, language, and formation

Onslow is used in English. Its origins include Germanic languages.

Onslow comes through Middle English Ondeslow and Old English *Andrǣd.

American usage and historical context

In the United States, 7 boys were recorded with the name Onslow between 1917 and 1917. Its highest annual count was 7 in 1917; its best national rank was #3,464 in 1917.

How common is Onslow?

Onslow had fewer than 5 recorded uses in 2025, so these figures use 1917, the last year it was published.

Among all babies, 1917: 1 in 287,000; 7 of 2,006,698 births
Among boys only: 1 in 132,000; <0.01% of boys
Rank, 1917: Unranked; Fewer than 5 uses
Coin-flip room size: 198,706 kids; Even odds of a second one

Where Onslow sits on the popularity scale

Rarest published (5 a year)#1 — Liam (20,818)

Chance at least one other child shares the name

If the other children were drawn at random from the 1917 national name distribution. Real classrooms cluster by region and community, so treat these as a floor, not a ceiling.

Class of 20Under 1%

Class of 30Under 1%

Grade of 100Under 1%

School of 500Under 1%

Put another way: gather 198,706 children born in 1917 and it's an even bet that one of them is another Onslow. In a class of 30 the chance is Under 1%.

When Onslows were born

Half of everyone ever recorded as Onslow was born before 1917 — so the typical Onslow is around 108 today.

Median birth year: 1917; About 108 years old
Biggest decade: 1910s; 100.0% of all use
Born in the last 25 years: 100.0%; A modern name
Recorded since 1950: 0; People you could plausibly meet

Choose a decade

1910s — 100.0% of all recorded uses (7).

Is Onslow rising or falling?

Rank movement and count movement can disagree — the number of distinct names in use keeps growing, so a name holding a steady count still slides down the list. Both are shown.

Rank vs 1 year ago: —; Not ranked then
Rank vs 5 years ago: New entry; Not ranked then
Rank vs 10 years ago: —; Not ranked then
Births vs 10 years ago: —; Not published both years
Share of its own peak: 0%; Peak was 1917 (7)
Years since peak: 108; Years
Year-to-year steadiness: Not enough data; Too few years
Best rank ever: #3,464; 1917

Spellings of Onslow

Onslow is not the most common spelling — Winslow is, with 75.3% against Onslow's 0.29%.

Winslow75.3%1,789
Oslo24.4%581
Onslow0.29%7

Grouped by closeness of spelling (up to two letter changes), same sex, with a floor on all-time use. It catches Sophia/Sofia and Aiden/Ayden, and misses spellings that sound alike but look different, like Sean and Shawn.

Onslow by the numbers

The raw record for each sex the name is used for.

As a boy's name

Rank in 2025: Unranked
Trend vs 5 yrs ago: —
Best rank ever: #3,464; 1917
Peak year: 1917; 7 that year
First recorded: 1917
Last recorded: 1917
All-time count: 7
Count in 2025: Under 5

Names similar to Onslow

Matched on shared beginnings and endings, similar length, and comparable popularity.

Darlow Edlow Ludlow Mellow Barlow Romellow Brownlow Low Willow Arlow Marlow Harlow Thurlow Winslow

Sibling names for Onslow

Names from the same era and popularity tier — the two things that make a sibling set feel deliberate — skipping lookalike spellings and shared initials.

For a sister

Albina Nelle Antonette Harriette Winnifred Maurine Johnie Dovie

For a brother

Regis Meyer Rosario Lyman Winfield Dorsey Granville Abe

Explore around Onslow

Top names of 1917, Onslow's peak year The 1910s in full Other names that peaked in 1917 Boys' names starting with O