A pen filler is an object used to fill a pen with INK. The crossword solutions for the term 'pen filler' are INK (3 letters), PIG (3 letters), HOG (3 letters), HOGS (4 letters), CON (3 letters), SHEEP (5 letters), and INDIAINK (8 letters). INK is a liquid or paste that contains pigments or dyes and is used to color a surface to produce an image, text, or design. PIG is a mammal with short legs, cloven hooves, bristles, and a snout used for digging. HOG is a large domesticated PIG, while HOGS is the plural form of HOG. CON is a swindle or fraud. SHEEP is a woolly ruminant mammal related to the goat. Lastly, INDIAINK is a black pigment made from lampblack, glue, and water.