I suppose if they were surrendering they would "throw in the towel", although it would have to be a fairly big towel to see it from any distance.

But on a serious note: If anything I am guilty of using terms loosely.

The idiom, "Raising the white flag", can have a inferred, accepted or popular meaning, and a legal meaning which according to the conclusion of link at bottom is in need of firm definition.

Some states explicitly recognize "Raising the White Flag" as a symbol of surrender, and some states do not.

France's Manual on the Law of Armed Conflict explains that ‘[a]n intention to surrender must be clearly expressed; by raising hands, throwing down weapons or waving a white flag’.

Dominican Republic's Military Manual accepts that once a white flag is waved this signals an intent to surrender.

The United States, for example, claims that ‘waving a white flag technically is not a sign of surrender, but signals a desire to negotiate and that ‘the hoisting of a white flag has no other legal meaning in the law of war’.

Canada's Code of Conduct states that ‘the showing of a white flag is not necessarily an expression of an intent to surrender’. The Teaching Manual for the armed forces of Côte d'Ivoire also explains that ‘the white flag is used to indicate the intention to negotiate and to protect the persons who negotiate. It does not necessarily indicate – as it is often believed – an intention to surrender’

International Humanitarian Law Databases ICRC (What we use to call Geneva Convention) Rule 58. Improper Use of the White Flag of Truce Definition Improper use refers to any use other than that for which the flag of truce was intended, namely a request to communicate, for example, in order to negotiate a cease-fire or to surrender.[13] Any other use, for example, to gain a military advantage over the enemy, is improper and unlawful.

Guidance on how a person expresses an intention to surrender is provided by the Official Commentary to Article 41(2) of Additional Protocol I:Footnote 99

In land warfare … a soldier who wishes to indicate that he is no longer capable of engaging in combat, or that he intends to cease combat, lays down his arms and raises his hands. Another way is to ceasefire, wave a white flag and emerge from a shelter with hands raised … If he is surprised, a combatant can raise his arms to indicate that he is surrendering, even though he may still be carrying weapons.

ICRC commentary to Rule 47 which, after citing ‘many military manuals’, explains that ‘[i]n land warfare, a clear intention to surrender is generally shown by laying down one's weapons and raising one's hands or by ‘displaying a white flag.

See Conclusion here.

I know this is TMI but what the hell.