to act like a manbaby

9.6

Behave in a very childish way as an adult

phrasal verb

Offensive

: hacerse el niñato (ofensivo, informal)

Whenever he doesn't get his way, he tends to act like a manbaby and sulk.

Examples

Stop acting like a manbaby and take responsibility for your mistake.
She was embarrassed when her brother acted like a manbaby in front of their friends.
Stop acting like a manbaby and take responsibility!
He always acts like a manbaby when things don't go his way.
When he didn't get the promotion, he acted like a manbaby, throwing a tantrum instead of discussing his feelings.
It's frustrating to see him act like a manbaby during serious discussions about our future.
Many adults act like manbabies when they fail to get their way, often causing tension in the group.

Synonyms

to throw one's toys out of the pram

vsto act like a manbaby

1 9.9

To behave in a childish sulky way after not getting what you want

is broader, meaning extreme childish behaviour by an adult not only sulking

to act like a booger brain

vsto act like a manbaby

Offensive

9.9

To behave in a silly and immature way

is more extreme, referring to very immature acting especially by adults

to act like a tosser

vsto act like a manbaby

Offensive

9.9

To behave rudely or foolishly in a way that annoys others

emphasises greater childishness and persistent immaturity rather than single poor acts

to be a wally

vsto act like a manbaby

Offensive

9.9

Act in a silly, embarrassing way

is stronger, meaning severe childish behaviour rather than mild foolishness

How Mature

mature

199 3.3

to grow up

∞ 1.3

to act like a manbaby

Offensive

9.6

Surface Forms

act like a manbaby infinitive

acted like a manbaby past

acted like a manbaby past participle

acting like a manbaby present participle

acts like a manbaby third person singular

Morphology

act + like + a + manbaby

The phrase follows a regular 'act like X' pattern and the nonce compound 'manbaby' transparently combines 'man' + 'baby', so a learner who knows those words can infer an adult male behaving like a baby (i.e., extremely immature). The composition is direct and predictable from the constituents and common cross-linguistically, so it should be understandable to a B1 learner.

Etymology

Act like a manbaby paints a clear picture: a grown man acting like a baby, crying, pouting, or asking for attention. So, it means 'to behave in an extremely immature or childish way'.