From:  http://www.bbc.co.uk/worldservice/learningenglish/language/2014/01/140109_todays_phrase_stand_tall.shtml

Stand tall

Snowy owls
Snowy owls' plumage (feathers) can vary from pure white to brown. Photo: BBC

Today's Phrase

When you say someone stands tall you mean they are confident and proud of themselves.
Examples:
Our athletes stand tall after winning many gold medals at this year's Olympics.
The critics thought the movie was awful, but its director stands tall as he heads for tonight's Oscars ceremony.

Take note

A tall order is something that is very difficult to do.
Example:
My teacher wants me to write three essays for next week. That's a tall order!

Interesting fact

Snowy owls use their white feathers to reflect sunlight, warning rivals of their presence, according to researchers at the University of Saskatchewan in Canada and the Museum of Natural Sciences in Spain.