Joining things or people together into proximity or contact
Encoding Strategies:
linguistic

join
to link / connect
+
-ar
verb suffix
Juntar means to bring together and turns the English word join2 (to link / connect2) into a verb1.
juntar
to bring together, to gather, to collect
To physically bring things together, forming some sort of collection or group.
Juntó todas las sillas alrededor de la mesaHe brought all the chairs together around the table
Los niños juntaron hojas secas en el jardínThe kids gathered dry leaves in the garden
juntarse
to meet up with, to get together with
When you "join yourself (with others)" you're literally bringing yourself together with other people (i.e. meeting up with them).
Me junté con mis amigos después del trabajoI met up with my friends after work
¿Nos juntamos el sábado para cenar?Shall we get together on Saturday for dinner?
to move closer together, to get together
When a group of people "join themselves together" they are literally moving closer to one another.
Júntense más para que quepan todos en la fotoMove closer together so everyone fits in the photo
Las nubes se fueron juntando hasta cubrir el cieloThe clouds gradually came together until they covered the sky