Yes, tinker is a Scrabble word!

Verb

1. Do random, unplanned work or activities or spend time idly

2. Work as a tinker or tinkerer

3. Try to fix or mend

Noun

1. A person who enjoys fixing and experimenting with machines and their parts

2. Formerly a person (traditionally a Gypsy) who traveled from place to place mending pots and kettles and other metal utensils as a way to earn a living

3. Small mackerel found nearly worldwide