Past Tense of “outgrow”
The past tense of outgrow is outgrew; the past participle is outgrown.
Why “outgrow” behaves this way
"Outgrow" combines "out-" with "grow," a verb whose irregular past forms (grow/grew/grown) descend from an Old English strong verb class marked by internal vowel change rather than an added ending — the same historical pattern responsible for "blow/blew/blown" and "know/knew/known." "Outgrow" first appears in written English by the 16th century, already carrying grow's full irregular conjugation with it. Historical dictionaries record the figurative sense (outgrowing a belief, a fear, a habit) developing not long after the literal physical sense, suggesting English speakers reached for this metaphor almost as soon as the compound verb existed, rather than the figurative use being a modern innovation.
Unlike some "out-" compounds that describe a single competitive act (like outbid or outrun), "outgrow" typically describes a gradual process completed over time — a child outgrowing shoes, a habit being outgrown — which lines up naturally with "grow" itself being a verb of gradual change rather than an instantaneous action. That semantic fit between prefix and base is part of why "outgrow" became one of the more common and durable "out-" compounds in everyday English, unlike rarer coinages that faded.
The common confusion
The confusion is almost never about the irregular forms themselves — most speakers know grow/grew/grown cold — but about whether "outgrown" needs "have" or can stand alone as an adjective ("my outgrown jacket" uses it adjectivally, no auxiliary needed, while "I have outgrown this jacket" is the full perfect-tense verb form).
How it's actually used
"Outgrow" spans both literal physical growth (children outgrowing clothes) and figurative development (outgrowing a habit, a friendship, or a fear), and the figurative sense is arguably now more common in adult writing than the literal one. Both senses use identical grew/grown forms — there is no separate conjugation for the metaphorical meaning. Parenting and child-development writing relies on the literal sense constantly (children outgrowing clothing sizes, outgrowing car seats, outgrowing cribs), while psychology and self-help writing leans almost entirely on the figurative sense (outgrowing an old identity, a toxic relationship, a limiting belief), and both registers coexist without any confusion because the surrounding context always makes clear which kind of growth is meant.
Across the tense system
The past participle "outgrown" does double duty as a true verb form ("she has outgrown her fears") and as a standalone adjective ("an outgrown habit"), which is common for -own/-own participles from strong verbs but worth noting since the adjectival use can look like it's missing an auxiliary when it isn't meant to have one. Because "outgrown" so easily functions as a plain adjective ("these outgrown boots"), writers describing an ongoing process should make sure to include the auxiliary "have" whenever they intend the full verb sense rather than the adjectival one, since dropping it can make a sentence read as an incomplete fragment.
Common real mistakes
The recurring error is using "outgrowed" by analogy with regular -ed verbs, especially from younger writers or ESL learners who haven't yet generalized "grow"'s irregular pattern to its compounds. A subtler error is writing "outgrew" where the sentence actually needs the participle ("I have outgrew this town" instead of "outgrown"). A further subtlety: because "outgrown" so often functions as an adjective ("an outgrown coat"), some writers mistakenly assume it can only be adjectival and avoid using it correctly as a full verb form in perfect-tense sentences, needlessly rephrasing around it. A further, more subtle point: "outgrow" always implies the earlier state genuinely no longer fits or applies, distinguishing it from simply "moving on from" something the person still fits or could return to.
Examples
- The toddler outgrew three pairs of shoes in one year.
- She has finally outgrown her fear of public speaking.
- They outgrew their starter apartment within eighteen months.
- By the time he was twelve, he had outgrown his older brother.
- The company has outgrown its original downtown office twice over.
- She outgrew her childhood shyness by her early twenties.
Memory trick
Pair it with its cousins: blow/blew/blown, know/knew/known, grow/grew/grown — outgrow just tacks "out-" onto that same family rhyme, so if you can say "she knew, she'd known," you can say "she outgrew, she'd outgrown."