nageln
to nail
To fasten something with one or more nails.
Er hat das Brett mit drei langen Stahlnägeln an der Wand festgenagelt.
He nailed the board to the wall with three long steel nails.

to nail / screw
Loading your saved state.
to nail
To fasten something with one or more nails.
Er hat das Brett mit drei langen Stahlnägeln an der Wand festgenagelt.
He nailed the board to the wall with three long steel nails.

The verb 'nageln' (to nail) is derived directly from the noun 'der Nagel' (the nail). So it literally describes the action you perform with a nail: fastening something.
Er suchte einen Hammer, um das Schild an den Baum zu nageln.
He looked for a hammer to nail the sign to the tree.
This word has a neutral, literal meaning (m01) and two very colloquial meanings (m02, m03). Whether it is about fastening something with nails or something else only becomes clear from the context. Be careful when using the colloquial meanings.
Kannst du mir helfen, das Regal an der Wand festzunageln?
Can you help me nail the shelf to the wall?
In the literal meaning, German often states what is nailed where. The construction is typically: 'etwas an/auf etwas (Akkusativ) nageln' (to nail something to/onto something).
Er nagelte das Plakat direkt an die Holzwand.
He nailed the poster directly to the wooden wall.
In this meaning, 'nageln' (to screw) is a very colloquial expression and is often perceived as vulgar. It should definitely be avoided in formal or polite conversations.
In seiner Erzählung benutzte er eine sehr direkte, vulgäre Sprache.
In his story, he used very direct, vulgar language.
In the colloquial meaning 'überführen' (to prove someone's guilt), the verb is often used in the context of crime or rule violations. Typically, 'der Täter' (the perpetrator), 'der Verdächtige' (the suspect), or 'der Betrüger' (the fraudster) is 'genagelt' (nailed).
Mit den neuen Beweismitteln konnte die Polizei den Dieb endlich nageln.
With the new evidence, the police were finally able to nail the thief.
to fuck
'ficken' and 'nageln' can both be used vulgarly for sexual intercourse. Both words are very direct and can quickly sound offensive or disrespectful. 'ficken' is especially crude and is very often heard as an insult or in coarse language. 'nageln' also sounds colloquial and often vulgar, but depending on the context it can also have a completely different, normal meaning: fastening something with nails. In polite conversations, you should avoid both words for the sexual meaning.

In dieser Serie reden die Figuren sehr derb und benutzen „nageln“ für Sex.
In this series, the characters speak very crudely and use 'nageln' to mean sex.
Im Streit hat er ein sehr vulgäres Wort wie „ficken“ benutzt.
During the argument, he used a very vulgar word like 'ficken'.