大不了

dàbùliǎo
  1. at worst; worse comes to worst
  2. serious

Wiktionary

Homographs

大不了 dàbuliǎo
  1. at worst; if worst comes to worst
  2. (usu. in the negative) serious; alarming

Examples

这没什么大不了的。

It's no big deal.

Source: Tatoeba

那没什么大不了的。

That's no big deal.

Source: Tatoeba

Entry Composition

=1 大 dà
  1. big; large; great
  2. older (than another person)
  3. eldest (as in 大姐 dàjiě)
  4. greatly; freely; fully
  5. (dialect) father
  6. (dialect) uncle (father's brother)
=1 大 dài see 大夫 dàifu
=2 不了 bùle no thanks (used to politely but informally decline)
=2 不了 bùliǎo
  1. (as a resultative verb suffix) unable to (do sth)
  2. (pattern: {verb} + 個 ge + ~) without end; incessantly