Let's assume that we have input file with list from your question. We can fill it using below command:

cat <<EOF > words+abbrs.txt

Administration

Admin.

Applied

Appl.

Administrative

Administ.

Approximate

Approx.

EOF

Creation of Markdown table is possible on Ubuntu using simple scripting as shown below:

• dumb step-by-step method

  
  

  # write table header
  
  echo "**Word** | **Abbreviation**" > table.md
  
  echo "- | -" >> table.md
  
  
  
  # extract odd lines as words to file words.txt
  
  awk 'NR%2==1' words+abbrs.txt > words.txt
  
  # extract even lines as abbreviations to file abbrs.txt
  
  awk 'NR%2==0' words+abbrs.txt > abbrs.txt
  
  
  
  # combine columns from words.txt and abbrs.txt with '|' separator
  
  paste -d '|' words.txt abbrs.txt >> table.md
  
  

  
  



• smart one-liner method (thanks to @steeldriver)

  
  

  { printf '%s
  
  ' '**Word** | **Abbreviation**' '-|-'; paste -d '|' - - < words+abbrs.txt; } > table.md
  
  

  
  

You will get the Markdown file with the following contents:

$ cat table.md 

**Word** | **Abbreviation**

- | -

Administration|Admin.

Applied|Appl.

Administrative|Administ.

Approximate|Approx.

So it will be rendered to HTML as

Word	Abbreviation
Administration	Admin.
Applied	Appl.
Administrative	Administ.
Approximate	Approx.

More info about used tools:

• man awk locally or online;


• man paste locally or online


• The GNU Awk User’s Guide


• BashGuide


• Advanced Bash-Scripting Guide