Regular Expressions 101

Non-Capturing Group(?:[a-z]+(?:_[a-z]+)*)

Character Class[a-z]+

+matches at least one character from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

Non-Capturing Group(?:_[a-z]+)*

*repeats the group contents below any number of times:

_the literal _ (95₁₀ / 137₈ / 5F₁₆)

Character Class[a-z]+

+matches at least one character from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

Negative Lookbehind(?<!_cat|_uom)

1st Alternative_cat

_catthe literal text _cat (case sensitive)

2nd Alternative_uom

_uomthe literal text _uom (case sensitive)

\ban ASCII word boundary

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

(?:[a-z]+(?:_[a-z]+)*)(?<!_cat|_uom)\b

New

xxx_yyyyyy_zzz_aaaaa
xxx_cat_zzz_aaaaa
xxx_yyyyyy_zzz_aaaaa_cat
xxx_yyyyyy_zzz_aaaaa_uom