Difference between location nouns and place/position nouns, 方位词 vs 处所词
方位次 are directions and positions with respect to something and include


relative directions


up/down - 上/下
left/right - 左/右
front/back - 前/后
in/out - 里/外

cardinal directions


north/south - 北/南
east/west - 东/西



which can prefix words like face, side, and corner to produce further position nouns.

处所词 are both places and proper nouns such as 上海.

They can be placed into 到。。。去 with nothing else and be grammatically correct such as 到上海去 and 到美国去, whereas general nouns, like 桌子, are not 处所词 as the sentence 到桌子去 is grammatically incorrect, although if 桌子那儿 is used instead of 桌子, this can be used as a place noun.

At least that is my general understanding of user6065's comment


  实用汉语语法＂４。３。２ 处所词 lg. place word。处所词的语法特点是：能做＂在＂＂到＂的宾语，能放在＂到。。。去＂的格式中。例如：在上海，到上海去。一般名词不能放在＂到。。。去＂的格式中。不能说＂到桌子去＂，＂到老张去＂，除非加上＂那儿＂使之成为处所短语，如＂到桌子那儿去＂，到老张那儿去＂。 所有的地名都是处所词，如：美国、亚洲、北京、天安门、颐和园，等等。＂邮局、宿舍、图书馆＂等既是名词，又是处所词。 ４。３。４ 方位词 noun of locality。方位词的语法特点基本上跟处所词相同。汉语共有１４个单音方位词：上、下、前、后、里、外、内、中、左、右、东、西、南、北。单音方位词加上＂边、面、头＂组成合成方位词。如：上边、后头、外边、左面、东头。所谓方位，既指空间，又指时间。＂屋前＂、＂屋后＂的＂前＂、＂后＂指处所，＂饭前＂、＂饭后＂的＂前＂、＂后＂指时间。名词加单方位词可以构成处所短语或时间短语。方位词不受数量短语的修饰，但是并不绝对排斥副词的修饰。例如：＂太前＂、＂太后＂；＂最前＂、＂最后＂。这中特点接近于形容词。单音方位词是一种黏着词，单用的能力很差；合成方位词比单音方位词要自由得多
  
  user6065


but my Chinese isn't good enough to be sure that I understood the comment correctly.