Alud vs. avalancha
The words 'alud' and 'avalancha' are both Spanish terms used to describe the phenomenon known as an avalanche. While they may seem similar, there are subtle differences in usage and connotation that distinguish one from the other.
Alud
The word 'alud' is generally used to indicate a landslide or a downfall, often used in a metaphorical sense. It refers not just to snow, but can also be used for mudslides, rockslides or any sudden large mass movement.
El alud de votos fue abrumador.
(The landslide of votes was overwhelming.)
Tras la tormenta, hubo un alud de lodo en la colina.
(After the storm, there was a mudslide on the hill.)
Avalancha
'Avalancha', on the other hand, is specifically used to indicate a snow avalanche. Aside from its literal meaning, it can also be metaphorically used to express a wave or onslaught of something.
La avalancha cubrió el pueblo de nieve.
(The avalanche covered the town with snow.)
Hubo una avalancha de quejas después del anuncio.
(There was an onslaught of complaints after the announcement.)
Summary
In summary, while both 'alud' and 'avalancha' can refer to an avalanche in Spanish, 'alud' has a broader application referring to any large or sudden mass movement including landslides and downfall, often used in a metaphorical context. On the other hand, 'avalancha' specifically refers to a snow avalanche but can also be metaphorically used for expressing an influx or wave of something.