Upright, solitary palm, fast growing 70-100' tall x 10' wide.
Trunk can be seen in multiple ways. One it is covered with of the old leaves and is called a skirt. Another common sight is clothed in only the leaf bases (also considered a skirt) or totally cleaned up naturally or with the help of pruning.
Cleaned up with pruning, not very natural looking but can be a safety issue as falling leaves are very heavy.
Leaves are palmate shaped, almost round, 3-5' wide and divided into 70-80 segments that extend well beyond half way to the base of the leaf. Tips of the leaves are pendulous and may have some fibers hanging off the tips.
Leaf stalks (about 3' long) are armed with 1-2" long reddish tinged recurved spines.
Here is a picture of the bases of the leaves still attached to the trunk. Some people like the look, others prefer a cleaned up look. Trunk can be 1-2' diameter. They can swell at the base but that is due to roots coming out of the stem and not from thickening of the stems. Palms are monocots and do not have secondary thickening or develop wood in the botanical sense of wood.
Flowers are small, greenish-white in long clusters 3-5' long. Fruit are 3/8" diameter, black shinny, with one seed. Borne way too high in the plant for me to get a picture.
Morrissey Blvd is a nice place to look at various palms. Also the building just off highway 1 at Airport Blvd at Westgate Dr in Watsonville. There are at least 5 different palms there.
Smaller examples of this might look like Brahea edulis but look at the trunk, Brahea leaves fall off clean leaving no petiole base attached.
Washingtonia filifera has a way fatter trunk, not just at the bottom but all along the stem. Canopy is also thinner and leaves more fibrous. You can see both Washingtonias on Morrissey Blvd.